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#include "bigint_string.h"
int bigInt_chAdd(char * ch, const char * c2, char * carry)
{ //return 0 = no error, return 1, 2, 3 = error!
switch (*carry)
{
case '0': switch (*c2)
{
case '0': return bigInt_chAdd0(ch, carry);
case '1': return bigInt_chAdd1(ch, carry);
case '2': return bigInt_chAdd2(ch, carry);
case '3': return bigInt_chAdd3(ch, carry);
case '4': return bigInt_chAdd4(ch, carry);
case '5': return bigInt_chAdd5(ch, carry);
case '6': return bigInt_chAdd6(ch, carry);
case '7': return bigInt_chAdd7(ch, carry);
case '8': return bigInt_chAdd8(ch, carry);
case '9': return bigInt_chAdd9(ch, carry);
default: return 2; //Error: c2 out of range
}
case '1': switch (*c2)
{
case '0': return bigInt_chAdd1(ch, carry);
case '1': return bigInt_chAdd2(ch, carry);
case '2': return bigInt_chAdd3(ch, carry);
case '3': return bigInt_chAdd4(ch, carry);
case '4': return bigInt_chAdd5(ch, carry);
case '5': return bigInt_chAdd6(ch, carry);
case '6': return bigInt_chAdd7(ch, carry);
case '7': return bigInt_chAdd8(ch, carry);
case '8': return bigInt_chAdd9(ch, carry);
case '9': return bigInt_chAdd10(ch, carry);
default: return 2; //Error: c2 out of range
}
default: return 3; //Error: *carry out of range
}
}
int bigInt_chAdd0(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '0'; return 0;
case '1': *carry = '0'; *ch = '1'; return 0;
case '2': *carry = '0'; *ch = '2'; return 0;
case '3': *carry = '0'; *ch = '3'; return 0;
case '4': *carry = '0'; *ch = '4'; return 0;
case '5': *carry = '0'; *ch = '5'; return 0;
case '6': *carry = '0'; *ch = '6'; return 0;
case '7': *carry = '0'; *ch = '7'; return 0;
case '8': *carry = '0'; *ch = '8'; return 0;
case '9': *carry = '0'; *ch = '9'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd1(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '1'; return 0;
case '1': *carry = '0'; *ch = '2'; return 0;
case '2': *carry = '0'; *ch = '3'; return 0;
case '3': *carry = '0'; *ch = '4'; return 0;
case '4': *carry = '0'; *ch = '5'; return 0;
case '5': *carry = '0'; *ch = '6'; return 0;
case '6': *carry = '0'; *ch = '7'; return 0;
case '7': *carry = '0'; *ch = '8'; return 0;
case '8': *carry = '0'; *ch = '9'; return 0;
case '9': *carry = '1'; *ch = '0'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd2(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '2'; return 0;
case '1': *carry = '0'; *ch = '3'; return 0;
case '2': *carry = '0'; *ch = '4'; return 0;
case '3': *carry = '0'; *ch = '5'; return 0;
case '4': *carry = '0'; *ch = '6'; return 0;
case '5': *carry = '0'; *ch = '7'; return 0;
case '6': *carry = '0'; *ch = '8'; return 0;
case '7': *carry = '0'; *ch = '9'; return 0;
case '8': *carry = '1'; *ch = '0'; return 0;
case '9': *carry = '1'; *ch = '1'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd3(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '3'; return 0;
case '1': *carry = '0'; *ch = '4'; return 0;
case '2': *carry = '0'; *ch = '5'; return 0;
case '3': *carry = '0'; *ch = '6'; return 0;
case '4': *carry = '0'; *ch = '7'; return 0;
case '5': *carry = '0'; *ch = '8'; return 0;
case '6': *carry = '0'; *ch = '9'; return 0;
case '7': *carry = '1'; *ch = '0'; return 0;
case '8': *carry = '1'; *ch = '1'; return 0;
case '9': *carry = '1'; *ch = '2'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd4(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '4'; return 0;
case '1': *carry = '0'; *ch = '5'; return 0;
case '2': *carry = '0'; *ch = '6'; return 0;
case '3': *carry = '0'; *ch = '7'; return 0;
case '4': *carry = '0'; *ch = '8'; return 0;
case '5': *carry = '0'; *ch = '9'; return 0;
case '6': *carry = '1'; *ch = '0'; return 0;
case '7': *carry = '1'; *ch = '1'; return 0;
case '8': *carry = '1'; *ch = '2'; return 0;
case '9': *carry = '1'; *ch = '3'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd5(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '5'; return 0;
case '1': *carry = '0'; *ch = '6'; return 0;
case '2': *carry = '0'; *ch = '7'; return 0;
case '3': *carry = '0'; *ch = '8'; return 0;
case '4': *carry = '0'; *ch = '9'; return 0;
case '5': *carry = '1'; *ch = '0'; return 0;
case '6': *carry = '1'; *ch = '1'; return 0;
case '7': *carry = '1'; *ch = '2'; return 0;
case '8': *carry = '1'; *ch = '3'; return 0;
case '9': *carry = '1'; *ch = '4'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd6(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '6'; return 0;
case '1': *carry = '0'; *ch = '7'; return 0;
case '2': *carry = '0'; *ch = '8'; return 0;
case '3': *carry = '0'; *ch = '9'; return 0;
case '4': *carry = '1'; *ch = '0'; return 0;
case '5': *carry = '1'; *ch = '1'; return 0;
case '6': *carry = '1'; *ch = '2'; return 0;
case '7': *carry = '1'; *ch = '3'; return 0;
case '8': *carry = '1'; *ch = '4'; return 0;
case '9': *carry = '1'; *ch = '5'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd7(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '7'; return 0;
case '1': *carry = '0'; *ch = '8'; return 0;
case '2': *carry = '0'; *ch = '9'; return 0;
case '3': *carry = '1'; *ch = '0'; return 0;
case '4': *carry = '1'; *ch = '1'; return 0;
case '5': *carry = '1'; *ch = '2'; return 0;
case '6': *carry = '1'; *ch = '3'; return 0;
case '7': *carry = '1'; *ch = '4'; return 0;
case '8': *carry = '1'; *ch = '5'; return 0;
case '9': *carry = '1'; *ch = '6'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd8(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '8'; return 0;
case '1': *carry = '0'; *ch = '9'; return 0;
case '2': *carry = '1'; *ch = '0'; return 0;
case '3': *carry = '1'; *ch = '1'; return 0;
case '4': *carry = '1'; *ch = '2'; return 0;
case '5': *carry = '1'; *ch = '3'; return 0;
case '6': *carry = '1'; *ch = '4'; return 0;
case '7': *carry = '1'; *ch = '5'; return 0;
case '8': *carry = '1'; *ch = '6'; return 0;
case '9': *carry = '1'; *ch = '7'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd9(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '0'; *ch = '9'; return 0;
case '1': *carry = '1'; *ch = '0'; return 0;
case '2': *carry = '1'; *ch = '1'; return 0;
case '3': *carry = '1'; *ch = '2'; return 0;
case '4': *carry = '1'; *ch = '3'; return 0;
case '5': *carry = '1'; *ch = '4'; return 0;
case '6': *carry = '1'; *ch = '5'; return 0;
case '7': *carry = '1'; *ch = '6'; return 0;
case '8': *carry = '1'; *ch = '7'; return 0;
case '9': *carry = '1'; *ch = '8'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chAdd10(char * ch, char * carry)
{ //return 0 = no error, return 1 = error!
switch (*ch)
{
case '0': *carry = '1'; *ch = '0'; return 0;
case '1': *carry = '1'; *ch = '1'; return 0;
case '2': *carry = '1'; *ch = '2'; return 0;
case '3': *carry = '1'; *ch = '3'; return 0;
case '4': *carry = '1'; *ch = '4'; return 0;
case '5': *carry = '1'; *ch = '5'; return 0;
case '6': *carry = '1'; *ch = '6'; return 0;
case '7': *carry = '1'; *ch = '7'; return 0;
case '8': *carry = '1'; *ch = '8'; return 0;
case '9': *carry = '1'; *ch = '9'; return 0;
default: return 1; //Error: *ch out of range
}
}
int bigInt_chSub(char * ch, const char * c2, char * borrow)
{ //return 0 = no error, return 4, 5, 6 = error!
switch (*borrow)
{
case '0': switch (*c2)
{
case '0': return bigInt_chSub0(ch, borrow);
case '1': return bigInt_chSub1(ch, borrow);
case '2': return bigInt_chSub2(ch, borrow);
case '3': return bigInt_chSub3(ch, borrow);
case '4': return bigInt_chSub4(ch, borrow);
case '5': return bigInt_chSub5(ch, borrow);
case '6': return bigInt_chSub6(ch, borrow);
case '7': return bigInt_chSub7(ch, borrow);
case '8': return bigInt_chSub8(ch, borrow);
case '9': return bigInt_chSub9(ch, borrow);
default: return 5; //Error: c2 out of range
}
case '1': switch (*c2)
{
case '0': return bigInt_chSub1(ch, borrow);
case '1': return bigInt_chSub2(ch, borrow);
case '2': return bigInt_chSub3(ch, borrow);
case '3': return bigInt_chSub4(ch, borrow);
case '4': return bigInt_chSub5(ch, borrow);
case '5': return bigInt_chSub6(ch, borrow);
case '6': return bigInt_chSub7(ch, borrow);
case '7': return bigInt_chSub8(ch, borrow);
case '8': return bigInt_chSub9(ch, borrow);
case '9': return bigInt_chSub10(ch, borrow);
default: return 5; //Error: c2 out of range
}
default: return 6; //Error: *borrow out of range
}
}
int bigInt_chSub0(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '0'; *ch = '0'; return 0;
case '1': *borrow = '0'; *ch = '1'; return 0;
case '2': *borrow = '0'; *ch = '2'; return 0;
case '3': *borrow = '0'; *ch = '3'; return 0;
case '4': *borrow = '0'; *ch = '4'; return 0;
case '5': *borrow = '0'; *ch = '5'; return 0;
case '6': *borrow = '0'; *ch = '6'; return 0;
case '7': *borrow = '0'; *ch = '7'; return 0;
case '8': *borrow = '0'; *ch = '8'; return 0;
case '9': *borrow = '0'; *ch = '9'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub1(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '9'; return 0;
case '1': *borrow = '0'; *ch = '0'; return 0;
case '2': *borrow = '0'; *ch = '1'; return 0;
case '3': *borrow = '0'; *ch = '2'; return 0;
case '4': *borrow = '0'; *ch = '3'; return 0;
case '5': *borrow = '0'; *ch = '4'; return 0;
case '6': *borrow = '0'; *ch = '5'; return 0;
case '7': *borrow = '0'; *ch = '6'; return 0;
case '8': *borrow = '0'; *ch = '7'; return 0;
case '9': *borrow = '0'; *ch = '8'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub2(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '8'; return 0;
case '1': *borrow = '1'; *ch = '9'; return 0;
case '2': *borrow = '0'; *ch = '0'; return 0;
case '3': *borrow = '0'; *ch = '1'; return 0;
case '4': *borrow = '0'; *ch = '2'; return 0;
case '5': *borrow = '0'; *ch = '3'; return 0;
case '6': *borrow = '0'; *ch = '4'; return 0;
case '7': *borrow = '0'; *ch = '5'; return 0;
case '8': *borrow = '0'; *ch = '6'; return 0;
case '9': *borrow = '0'; *ch = '7'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub3(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '7'; return 0;
case '1': *borrow = '1'; *ch = '8'; return 0;
case '2': *borrow = '1'; *ch = '9'; return 0;
case '3': *borrow = '0'; *ch = '0'; return 0;
case '4': *borrow = '0'; *ch = '1'; return 0;
case '5': *borrow = '0'; *ch = '2'; return 0;
case '6': *borrow = '0'; *ch = '3'; return 0;
case '7': *borrow = '0'; *ch = '4'; return 0;
case '8': *borrow = '0'; *ch = '5'; return 0;
case '9': *borrow = '0'; *ch = '6'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub4(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '6'; return 0;
case '1': *borrow = '1'; *ch = '7'; return 0;
case '2': *borrow = '1'; *ch = '8'; return 0;
case '3': *borrow = '1'; *ch = '9'; return 0;
case '4': *borrow = '0'; *ch = '0'; return 0;
case '5': *borrow = '0'; *ch = '1'; return 0;
case '6': *borrow = '0'; *ch = '2'; return 0;
case '7': *borrow = '0'; *ch = '3'; return 0;
case '8': *borrow = '0'; *ch = '4'; return 0;
case '9': *borrow = '0'; *ch = '5'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub5(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '5'; return 0;
case '1': *borrow = '1'; *ch = '6'; return 0;
case '2': *borrow = '1'; *ch = '7'; return 0;
case '3': *borrow = '1'; *ch = '8'; return 0;
case '4': *borrow = '1'; *ch = '9'; return 0;
case '5': *borrow = '0'; *ch = '0'; return 0;
case '6': *borrow = '0'; *ch = '1'; return 0;
case '7': *borrow = '0'; *ch = '2'; return 0;
case '8': *borrow = '0'; *ch = '3'; return 0;
case '9': *borrow = '0'; *ch = '4'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub6(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '4'; return 0;
case '1': *borrow = '1'; *ch = '5'; return 0;
case '2': *borrow = '1'; *ch = '6'; return 0;
case '3': *borrow = '1'; *ch = '7'; return 0;
case '4': *borrow = '1'; *ch = '8'; return 0;
case '5': *borrow = '1'; *ch = '9'; return 0;
case '6': *borrow = '0'; *ch = '0'; return 0;
case '7': *borrow = '0'; *ch = '1'; return 0;
case '8': *borrow = '0'; *ch = '2'; return 0;
case '9': *borrow = '0'; *ch = '3'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub7(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '3'; return 0;
case '1': *borrow = '1'; *ch = '4'; return 0;
case '2': *borrow = '1'; *ch = '5'; return 0;
case '3': *borrow = '1'; *ch = '6'; return 0;
case '4': *borrow = '1'; *ch = '7'; return 0;
case '5': *borrow = '1'; *ch = '8'; return 0;
case '6': *borrow = '1'; *ch = '9'; return 0;
case '7': *borrow = '0'; *ch = '0'; return 0;
case '8': *borrow = '0'; *ch = '1'; return 0;
case '9': *borrow = '0'; *ch = '2'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub8(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '2'; return 0;
case '1': *borrow = '1'; *ch = '3'; return 0;
case '2': *borrow = '1'; *ch = '4'; return 0;
case '3': *borrow = '1'; *ch = '5'; return 0;
case '4': *borrow = '1'; *ch = '6'; return 0;
case '5': *borrow = '1'; *ch = '7'; return 0;
case '6': *borrow = '1'; *ch = '8'; return 0;
case '7': *borrow = '1'; *ch = '9'; return 0;
case '8': *borrow = '0'; *ch = '0'; return 0;
case '9': *borrow = '0'; *ch = '1'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub9(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '1'; return 0;
case '1': *borrow = '1'; *ch = '2'; return 0;
case '2': *borrow = '1'; *ch = '3'; return 0;
case '3': *borrow = '1'; *ch = '4'; return 0;
case '4': *borrow = '1'; *ch = '5'; return 0;
case '5': *borrow = '1'; *ch = '6'; return 0;
case '6': *borrow = '1'; *ch = '7'; return 0;
case '7': *borrow = '1'; *ch = '8'; return 0;
case '8': *borrow = '1'; *ch = '9'; return 0;
case '9': *borrow = '0'; *ch = '0'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_chSub10(char * ch, char * borrow)
{ //return 0 = no error, return 4 = error!
switch (*ch)
{
case '0': *borrow = '1'; *ch = '0'; return 0;
case '1': *borrow = '1'; *ch = '1'; return 0;
case '2': *borrow = '1'; *ch = '2'; return 0;
case '3': *borrow = '1'; *ch = '3'; return 0;
case '4': *borrow = '1'; *ch = '4'; return 0;
case '5': *borrow = '1'; *ch = '5'; return 0;
case '6': *borrow = '1'; *ch = '6'; return 0;
case '7': *borrow = '1'; *ch = '7'; return 0;
case '8': *borrow = '1'; *ch = '8'; return 0;
case '9': *borrow = '1'; *ch = '9'; return 0;
default: return 4; //Error: *ch out of range
}
}
int bigInt_parse(const char * str, int * p_or_n, int * i_qty, int * d_qty, int * dot_pos)
{ //return 0 = no error, str is a bigint string, return 99, 7, 8, 9 = error!
if (0 == str)
return 99; //Error: nullptr is not allowed.
int index = 0; //index of str.
switch (str[index])
{
case '-': *p_or_n = -1; index++; break; //negative number and bypass the '-'
case '+': index++; //bypass the '+'
default: *p_or_n = 1; //positive number
}
*i_qty = 0; //integer part char qty
*d_qty = 0; //decimal part char qty
*dot_pos = -1; //initialized as a not possible value.
int dot_found = 0; //'.' found in the str
while (str[index] != '\0')
{
switch (str[index])
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9': dot_found ? ++(*d_qty) : ++(*i_qty);
break;
case '.': if (++dot_found > 1)
return 7; //Error: too many '.'
*dot_pos = index;
break;
default: return 8; //Error: unexpected char found
}
index++;
}
if (*i_qty == 0 && *d_qty == 0)
return 9; //Error: no valid number found
if (*dot_pos == -1) //there is no '.' in the str, str is an integer
*dot_pos = index; //dot_pos set at '\0'(str end) for "no dot" integer
////ignore excessive '0' in the end of decimal part
//if (*i_qty > 0)
// while (*d_qty > 0 && str[*dot_pos + *d_qty] == '0')
// --(*d_qty);
//else
// while (*d_qty > 1 && str[*dot_pos + *d_qty] == '0')
// --(*d_qty); //leave 1 char at least
////ignore excessive '0' in the begining of integeral part
//if (*d_qty > 0)
// while (*i_qty > 0 && str[*dot_pos - *i_qty] == '0')
// --(*i_qty);
//else
// while (*i_qty > 1 && str[*dot_pos - *i_qty] == '0')
// --(*i_qty); //leave 1 char at least
return 0;
}
int bigInt_chInc(char * ch)
{ //return 0 = no error, return 10 = error! return 11 = Carry discarded!
switch (*ch)
{
case '0': *ch = '1'; return 0;
case '1': *ch = '2'; return 0;
case '2': *ch = '3'; return 0;
case '3': *ch = '4'; return 0;
case '4': *ch = '5'; return 0;
case '5': *ch = '6'; return 0;
case '6': *ch = '7'; return 0;
case '7': *ch = '8'; return 0;
case '8': *ch = '9'; return 0;
case '9': *ch = '0'; return 11; //Error: Carry discarded
default: return 10; //Error: *ch out of range
}
}
int bigInt_chDec(char * ch)
{ //return 0 = no error, return 12 = error! return 13 = borrow discarded!
switch (*ch)
{
case '0': *ch = '9'; return 13; //Error: borrow discarded
case '1': *ch = '0'; return 0;
case '2': *ch = '1'; return 0;
case '3': *ch = '2'; return 0;
case '4': *ch = '3'; return 0;
case '5': *ch = '4'; return 0;
case '6': *ch = '5'; return 0;
case '7': *ch = '6'; return 0;
case '8': *ch = '7'; return 0;
case '9': *ch = '8'; return 0;
default: return 12; //Error: *ch out of range
}
}
int bigInt_strTailAlignedAdd(char * s1, const int * h1, const int * t1,
const char * s2, const int * h2, const int * t2,
char * carry)
{ //return 0 = no error, return 19 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
if (*t1 - *h1 < *t2 - *h2)
return 19; //Error: not allowed: *t1 - *h1 < *t2 - *h2
const int s2CharQty = *t2 - *h2 + 1;
for (int i = 0; i < s2CharQty; ++i)
if (tempRetVal = bigInt_chAdd(&s1[*t1 - i], &s2[*t2 - i], carry))
return tempRetVal; //Error: bigInt_chAdd() returned error!
const char c2 = '0';
for (int temp_t1 = *t1 - s2CharQty; *carry == '1' && temp_t1 >= *h1; --temp_t1)
if (tempRetVal = bigInt_chAdd(&s1[temp_t1], &c2, carry))
return tempRetVal; //Error: bigInt_chAdd() returned error!
return 0;
}
int bigInt_strTailAlignedSub(char * s1, const int * h1, const int * t1,
const char * s2, const int * h2, const int * t2,
char * borrow)
{ //return 0 = no error, return 20 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
if (*t1 - *h1 < *t2 - *h2)
return 20; //Error: not allowed: *t1 - *h1 < *t2 - *h2
const int s2CharQty = *t2 - *h2 + 1;
for (int i = 0; i < s2CharQty; ++i)
if (tempRetVal = bigInt_chSub(&s1[*t1 - i], &s2[*t2 - i], borrow))
return tempRetVal; //Error: bigInt_chSub() returned error!
const char c2 = '0';
for (int temp_t1 = *t1 - s2CharQty; *borrow == '1' && temp_t1 >= *h1; --temp_t1)
if (tempRetVal = bigInt_chSub(&s1[temp_t1], &c2, borrow))
return tempRetVal; //Error: bigInt_chSub() returned error!
return 0;
}
int bigInt_strTailAlignedSubTry(const char * s1, const int * h1, const int * t1,
const char * s2, const int * h2, const int * t2,
char * borrow)
{ //return 0 = no error, return 21 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
if (*t1 - *h1 < *t2 - *h2)
return 21; //Error: not allowed: *t1 - *h1 < *t2 - *h2
const int s2CharQty = *t2 - *h2 + 1;
char tempChar;
for (int i = 0; i < s2CharQty; ++i)
{
tempChar = s1[*t1 - i];
if (tempRetVal = bigInt_chSub(&tempChar, &s2[*t2 - i], borrow))
return tempRetVal; //Error: bigInt_chSub() returned error!
}
const char c2 = '0';
for (int temp_t1 = *t1 - s2CharQty; *borrow == '1' && temp_t1 >= *h1; --temp_t1)
{
tempChar = s1[temp_t1];
if (tempRetVal = bigInt_chSub(&tempChar, &c2, borrow))
return tempRetVal; //Error: bigInt_chSub() returned error!
}
return 0;
}
int bigInt_chSet(char * s1, const int * h1, const int * t1, char ch)
{ //return 0 = no error.
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_chValidate(ch))
return tempRetVal; //Error: wrong ch.
for (int i = *h1; i <= *t1; ++i)
s1[i] = ch;
return 0;
}
int bigInt_chSetAtPosition(char * s1, int * h1, int * t1, const int * s1Size,
const int * position, char ch)
{ //return 0 = no error, return 22 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_chValidate(ch))
return tempRetVal; //Error: wrong ch.
if (*position < 0 || *position < *h1 - 1 || *position > *t1 + 1 || *position >= *s1Size)
return 22; //Error: not a reasonable position.
if (*position == *h1 - 1)
--(*h1);
if (*position == *t1 + 1)
++(*t1);
s1[*position] = ch;
return 0;
}
int bigInt_chSetBeforeHead(char * s1, int * h1, int * t1, const int * s1Size, char ch)
{ //return 0 = no error
int tempRetVal;
int position = *h1 - 1;
if (tempRetVal = bigInt_chSetAtPosition(s1, h1, t1, s1Size, &position, ch))
return tempRetVal;
return 0;
}
int bigInt_chSetAfterTail(char * s1, int * h1, int * t1, const int * s1Size, char ch)
{ //return 0 = no error
int tempRetVal;
int position = *t1 + 1;
if (tempRetVal = bigInt_chSetAtPosition(s1, h1, t1, s1Size, &position, ch))
return tempRetVal;
return 0;
}
int bigInt_chSequentialSetting(char * s1, int * h1, int * t1, const int * s1Size,
int * setPosition, char ch)
{ //return 0 = no error.
int tempRetVal;
if (tempRetVal = bigInt_chSetAtPosition(s1, h1, t1, s1Size, setPosition, ch))
return tempRetVal;
++(*setPosition);
return 0;
}
int bigInt_chValidate(char ch)
{ //return 0 = no error, return 23 = error!
switch (ch)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '.':
case '-':
case '+':
case '\0': return 0;
default: return 23; //Error: wrong ch.
}
}
int bigInt_headTailValidate(int head, int tail)
{ //return 0 = no error, return 24 = error!
if (head < 0 || tail < 0 || tail - head < 0)
return 24; //Error: wrong parameter.
return 0;
}
int bigInt_strCopy(char * s1, const int * h1, const int * t1,
const char * s2, const int * h2, const int * t2)
{ //return 0 = no error, return 25 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
if (*t1 - *h1 != *t2 - *h2)
return 25; //Error: not allowed: *t1 - *h1 != *t2 - *h2
if (s1 + *h1 < s2 + *h2) //move start from head to tail
for (int i = *h1, j = *h2; i <= *t1 && j <= *t2; ++i, ++j)
s1[i] = s2[j];
else if (s1 + *h1 > s2 + *h2) //move start from tail to head
for (int i = *t1, j = *t2; i >= *h1 && j >= *h2; --i, --j)
s1[i] = s2[j];
else
; // desti == source ? do nothing!
return 0;
}
int bigInt_findNewHead(const char * s1, int * h1, const int * t1)
{ //return 0 = no error
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
while (s1[*h1] == '0' && *h1 < *t1)
++(*h1);
return 0;
}
int bigInt_findNewTail(const char * s1, const int * h1, int * t1)
{ //return 0 = no error
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
while (s1[*t1] == '0' && *t1 > *h1)
--(*t1);
return 0;
}
int bigInt_findDotPosition(const char * s1, const int * h1, const int * t1,
int * dotPosition)
{ //return 0 = no error, return 26 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
*dotPosition = -1;
int dotCount = 0;
for (int i = *h1; i <= *t1; ++i)
{
if (s1[i] == '.')
{
*dotPosition = i;
++dotCount;
}
}
if (dotCount > 1)
return 26; //Error: too many dot
return 0;
}
int bigInt_isZero(const char * s1, const int * h1, const int * t1,
char * isZero)
{ //return 0 = no error
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
*isZero = 'T';
for (int i = *h1; i <= *t1; ++i)
{
switch (s1[i])
{
case '0':
case '.':
case '+':
case '-':
case '\0': continue;
default: *isZero = 'F'; break;
}
}
return 0;
}
int bigInt_copyToBufferPosition(const char * str, int i_qty, int d_qty, int dot_pos,
int aligned_i_size, int aligned_d_size, int safeSpaceBeforeHead, int safeSpaceAfterTail,
char * buffer, int bufferSize, int * head, int * tail, const char * position)
{ //return 0 = no error, return 34, 35, 36 = error!
if (i_qty < 0 || d_qty < 0 || dot_pos < 0 || aligned_i_size < 0 || aligned_d_size < 0)
return 34; //Error: wrong parameter
if (bufferSize < safeSpaceBeforeHead + aligned_i_size + aligned_d_size + safeSpaceAfterTail)
return 35; //Error: bufferSize is not enough
int tempRetVal;
int nextIndexToFill;
if (position[0] == 's') //fill at a position close to the start of the buffer.
nextIndexToFill = safeSpaceBeforeHead;
else if (position[0] == 'e') //fill at a position close to the end of the buffer.
nextIndexToFill = bufferSize - safeSpaceAfterTail - aligned_d_size - aligned_i_size;
else
return 36;
//insert '0' before integer parts.
*head = nextIndexToFill;
if (aligned_i_size > i_qty)
{
int frontZeroQty = aligned_i_size - i_qty;
int fillZeroStart = nextIndexToFill;
int fillZeroEnd = fillZeroStart + frontZeroQty - 1;
if (tempRetVal = bigInt_chSet(buffer, &fillZeroStart, &fillZeroEnd, '0'))
return tempRetVal;
nextIndexToFill = fillZeroEnd + 1;
}
//copy integer parts
if (i_qty > 0)
{
int fillIntegerStart = nextIndexToFill;
int fillIntegerEnd = fillIntegerStart + i_qty - 1;
int integer_head = dot_pos - i_qty;
int integer_tail = dot_pos - 1;
if (tempRetVal = bigInt_strCopy(buffer, &fillIntegerStart, &fillIntegerEnd,
str, &integer_head, &integer_tail))
return tempRetVal;
nextIndexToFill = fillIntegerEnd + 1;
}
//copy decimal parts
if (d_qty > 0)
{
int fillDecimalStart = nextIndexToFill;
int fillDecimalEnd = fillDecimalStart + d_qty - 1;
int decimal_head = dot_pos + 1;
int decimal_tail = dot_pos + d_qty;
if (tempRetVal = bigInt_strCopy(buffer, &fillDecimalStart, &fillDecimalEnd,
str, &decimal_head, &decimal_tail))
return tempRetVal;
nextIndexToFill = fillDecimalEnd + 1;
}
//insert '0' after decimal parts.
if (aligned_d_size > d_qty)
{
int rearZeroQty = aligned_d_size - d_qty;
int fillZeroStart = nextIndexToFill;
int fillZeroEnd = fillZeroStart + rearZeroQty - 1;
if (tempRetVal = bigInt_chSet(buffer, &fillZeroStart, &fillZeroEnd, '0'))
return tempRetVal;
nextIndexToFill = fillZeroEnd + 1;
}
*tail = nextIndexToFill - 1;
if (tempRetVal = bigInt_headTailValidate(*head, *tail)) //double check only
return tempRetVal; //Error: something wrong.
return 0;
}
int bigInt_chInsertFromHead(char * s1, int * h1, const int * t1, const int * s1Size,
const int * insertBeforeThisPos, char insertCh)
{ //return 0 = no error, return 37, 38, 39 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (*insertBeforeThisPos < *h1 || *insertBeforeThisPos > *t1 + 1)
return 37; //Error: wrong insert position
if (*t1 >= *s1Size)
return 38; //Error: out of space
if ((*h1 - 1) < 0)
return 39; //Error: out of space
//move chars to left if necessary.
if (*insertBeforeThisPos != *h1)
{
int sourceHead = *h1;
int sourceTail = *insertBeforeThisPos - 1;
int destiHead = *h1 - 1;
int destiTail = *insertBeforeThisPos - 2;
if (tempRetVal = bigInt_strCopy(s1, &destiHead, &destiTail,
s1, &sourceHead, &sourceTail))
return tempRetVal;
}
int pos = *insertBeforeThisPos - 1;
char ch = insertCh;
if (tempRetVal = bigInt_chSet(s1, &pos, &pos, ch))
return tempRetVal;
--(*h1);
return 0;
}
int bigInt_chInsertFromTail(char * s1, const int * h1, int * t1, const int * s1Size,
const int * insertBeforeThisPos, char insertCh)
{ //return 0 = no error, return 40, 41 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_chValidate(insertCh))
return tempRetVal; //Error: wrong ch
if (*insertBeforeThisPos < *h1 || *insertBeforeThisPos > *t1 + 1)
return 40; //Error: wrong insert position
if ((*t1 + 1) >= *s1Size)
return 41; //Error: out of space
//move chars to right if necessary.
if (*insertBeforeThisPos != *t1 + 1)
{
int sourceHead = *insertBeforeThisPos;
int sourceTail = *t1;
int destiHead = *insertBeforeThisPos + 1;
int destiTail = *t1 + 1;
if (tempRetVal = bigInt_strCopy(s1, &destiHead, &destiTail,
s1, &sourceHead, &sourceTail))
return tempRetVal;
}
int pos = *insertBeforeThisPos;
char ch = insertCh;
if (tempRetVal = bigInt_chSet(s1, &pos, &pos, ch))
return tempRetVal;
++(*t1);
return 0;
}
int bigInt_add(const char * s1, const char * s2, int * resultInBuffer,
char * buffer, const int * bufferSize)
{ //return 0 = no error.
int tempRetVal;
if (tempRetVal = bigInt_addOrSub(s1, s2, resultInBuffer,
buffer, bufferSize, "Add"))
return tempRetVal;
return 0;
}
int bigInt_sub(const char * s1, const char * s2, int * resultInBuffer,
char * buffer, const int * bufferSize)
{ //return 0 = no error.
int tempRetVal;
if (tempRetVal = bigInt_addOrSub(s1, s2, resultInBuffer,
buffer, bufferSize, "Sub"))
return tempRetVal;
return 0;
}
int bigInt_addOrSub(const char * str1, const char * str2, int * resultInBuffer,
char * buffer, const int * bufferSize,
const char * toDo)
{ //return 0 = no error, return 45, 46, 47, 48, 49, 50, 51, 52 = error!
int tempRetVal;
int pn1, iq1, dq1, dp1;
if (tempRetVal = bigInt_parse(str1, &pn1, &iq1, &dq1, &dp1))
return tempRetVal;
int pn2, iq2, dq2, dp2;
if (tempRetVal = bigInt_parse(str2, &pn2, &iq2, &dq2, &dp2))
return tempRetVal;
//consider toDo
switch (toDo[0])
{
case 'S': pn2 = -pn2; //change s1 - s2 to s1 + (-s2)
case 'A': break; //Add is default operation
default: return 45; //Error: wrong parameter!
}
//align the size of str1 and str2
int aligned_i_size = (iq1 > iq2) ? iq1 : iq2;
int aligned_d_size = (dq1 > dq2) ? dq1 : dq2;
const int safeSpaceBeforeHead = 4;
//extraSpaceInFront is required when you inserting 'carry', '.' or '-'
const int safeSpaceAfterTail = 4;
//extraSpaceAtRear is required when you inserting '.' or '\0'
//copy str1 to a position close to the end of the buffer,
//digit chars only, and name as s1.
char * s1 = buffer;
int s1Size = *bufferSize;
int h1, t1;
const char * s1Position = "end of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str1, iq1, dq1, dp1,
aligned_i_size, aligned_d_size, safeSpaceBeforeHead, safeSpaceAfterTail,
s1, s1Size, &h1, &t1, s1Position))
return tempRetVal;
//copy str2 to a position close to the start of the buffer,
//digit chars only, and name as s2.
char * s2 = buffer;
int s2Size = *bufferSize;
int h2, t2;
const char * s2Position = "start of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str2, iq2, dq2, dp2,
aligned_i_size, aligned_d_size, safeSpaceBeforeHead, safeSpaceAfterTail,
s2, s2Size, &h2, &t2, s2Position))
return tempRetVal;
//check free space in buffer
int freeSpaceInBuffer = *bufferSize - (t1 - h1 + 1) - (t2 - h2 + 1)
- safeSpaceBeforeHead * 2 - safeSpaceAfterTail * 2;
if (freeSpaceInBuffer < 0)
return 46; //Error: not enough bufferSize
//add or sub decided by pn1 and pn2
//to save bufferSize, s1 or s2 may destroyed during add or sub.
char * s3 = buffer;
int s3Size = *bufferSize;
int h3, t3, pn3;
if (pn1 * pn2 == 1)
{
if (tempRetVal = bigInt_addWithSameSign(s1, &s1Size, &h1, &t1, &pn1,
s2, &s2Size, &h2, &t2, &pn2, s3, &s3Size, &h3, &t3, &pn3))
return tempRetVal;
}
else if (pn1 * pn2 == -1)
{
if (tempRetVal = bigInt_addWithOppositeSigns(s1, &s1Size, &h1, &t1, &pn1,
s2, &s2Size, &h2, &t2, &pn2, s3, &s3Size, &h3, &t3, &pn3))
return tempRetVal;
}
else
{
return 47; // impossible, something wrong.
}
//make a readable s3, read friendly for human.
int dq3 = aligned_d_size;
if (tempRetVal = bigInt_makeFinishStr(s3, &s3Size,
&h3, &t3, &dq3, &pn3))
return tempRetVal;
//calc result index in buffer
*resultInBuffer = (int)(s3 - buffer + h3);
return 0;
}
int bigInt_addWithSameSign(
char * s1, const int * s1Size, int * h1, int * t1, int * pn1,
char * s2, const int * s2Size, int * h2, int * t2, int * pn2,
char * s3, const int * s3Size, int * h3, int * t3, int * pn3)
{ //return 0 = no error, return 54 = error!
int tempRetVal;
char carry = '0';
if (tempRetVal = bigInt_strTailAlignedAdd(s1, h1, t1,
s2, h2, t2, &carry))
return tempRetVal;
//write '1' ahead of h1 if carry == '1'
if (carry == '1')
{
if (tempRetVal = bigInt_chSetBeforeHead(s1, h1, t1, s1Size, carry))
return tempRetVal;
carry = '0';
}
*h3 = (int)(s1 - s3 + *h1);
*t3 = (int)(s1 - s3 + *t1);
if (*pn1 == 1 && *pn2 == 1)
*pn3 = 1;
else if (*pn1 == -1 && *pn2 == -1)
*pn3 = -1;
else
return 54; // Error: not alloweded in this function.
return 0;
}
int bigInt_addWithOppositeSigns(
char * s1, const int * s1Size, int * h1, int * t1, int * pn1,
char * s2, const int * s2Size, int * h2, int * t2, int * pn2,
char * s3, const int * s3Size, int * h3, int * t3, int * pn3)
{ //return 0 = no error, return 55, 56, 57, 58 = error!
int tempRetVal;
char borrow = '0';
if (tempRetVal = bigInt_strTailAlignedSubTry(s1, h1, t1,
s2, h2, t2, &borrow))
return tempRetVal;
if (borrow == '0')
{ // absolute s1 >= absolute s2, do: |s1| - |s2|
borrow = '0';
if (tempRetVal = bigInt_strTailAlignedSub(s1, h1, t1,
s2, h2, t2, &borrow))
return tempRetVal;
*h3 = (int)(s1 - s3 + *h1);
*t3 = (int)(s1 - s3 + *t1);
if (*pn1 == 1 && *pn2 == -1)
*pn3 = 1;
else if (*pn1 == -1 && *pn2 == 1)
*pn3 = -1;
else
return 55; // Error: not alloweded in this function.
}
else if (borrow == '1')
{ // absolute s1 < absolute s2, do: |s2| - |s1|
borrow = '0';
if (tempRetVal = bigInt_strTailAlignedSub(s2, h2, t2,
s1, h1, t1, &borrow))
return tempRetVal;
if (borrow == '1')
return 56; // impossible, something wrong.
*h3 = (int)(s2 - s3 + *h2);
*t3 = (int)(s2 - s3 + *t2);
if (*pn1 == 1 && *pn2 == -1)
*pn3 = -1;
else if (*pn1 == -1 && *pn2 == 1)
*pn3 = 1;
else
return 57; // Error: not alloweded in this function.
}
else
{
return 58; // impossible, something wrong.
}
return 0;
}
int bigInt_makeFinishStr(char * s3, const int * s3Size,
int * h3, int * t3, int * dq3, int * pn3)
{ //return 0 = no error.
int tempRetVal;
int insertBeforeThisPos;
char insertCh;
//find if there is '.' already exist in s3.
int dotPosition = -1; // -1 means no dot
if (tempRetVal = bigInt_findDotPosition(s3, h3, t3, &dotPosition))
return tempRetVal;
//insert '.' if dot not found, and there's decimal parts
if (dotPosition == -1 && *dq3 > 0)
{
int insertZeroQtyBeforeHead = *dq3 - (*t3 - *h3);
if (insertZeroQtyBeforeHead > 0)
{
int tail = *h3 - 1;
int head = tail + 1 - insertZeroQtyBeforeHead;
char setCh = '0';
if (tempRetVal = bigInt_chSet(s3, &head, &tail, setCh))
return tempRetVal;
*h3 = head;
}
insertBeforeThisPos = *t3 + 1 - *dq3;
insertCh = '.';
if (insertBeforeThisPos - *h3 > *t3 - insertBeforeThisPos)
{
if (tempRetVal = bigInt_chInsertFromTail(s3, h3, t3, s3Size,
&insertBeforeThisPos, insertCh))
return tempRetVal;
dotPosition = insertBeforeThisPos;
}
else
{
if (tempRetVal = bigInt_chInsertFromHead(s3, h3, t3, s3Size,
&insertBeforeThisPos, insertCh))
return tempRetVal;
dotPosition = insertBeforeThisPos - 1;
}
}
// unreasonable case 1: dot at head, may occur by incoming dot exist.
if (dotPosition == *h3)
{ //attention: use bigInt_chInsertFromTail() to avoid change of *h3
insertBeforeThisPos = *h3;
insertCh = '0';
if (tempRetVal = bigInt_chInsertFromTail(s3, h3, t3, s3Size,
&insertBeforeThisPos, insertCh))
return tempRetVal;
++dotPosition;
}
// unreasonable case 2: dot at tail, may occur by incoming dot exist.
if (dotPosition == *t3)
{
--(*t3);
dotPosition = -1;
}
//find new head and tail.
if (dotPosition == -1) // -1 means no dot
{
if (tempRetVal = bigInt_findNewHead(s3, h3, t3))
return tempRetVal;
}
else
{
int tailOfIntegerPart = dotPosition - 1;
if (tempRetVal = bigInt_findNewHead(s3, h3, &tailOfIntegerPart))
return tempRetVal;
int headOfDecimalPart = dotPosition + 1;
if (tempRetVal = bigInt_findNewTail(s3, &headOfDecimalPart, t3))
return tempRetVal;
if (*t3 == headOfDecimalPart && s3[*t3] == '0')
*t3 = tailOfIntegerPart;
}
//write '-' ahead of h3
//only if '-' not exist and pn3 == -1 and value is not Zero.
char isZero;
if (tempRetVal = bigInt_isZero(s3, h3, t3, &isZero))
return tempRetVal;
if (s3[*h3] != '-' && * pn3 == -1 && isZero == 'F')
{
if (tempRetVal = bigInt_chSetBeforeHead(s3, h3, t3, s3Size, '-'))
return tempRetVal;
}
//append '\0' after t3.
if (tempRetVal = bigInt_chSetAfterTail(s3, h3, t3, s3Size, '\0'))
return tempRetVal;
return 0;
}
int bigInt_strTailAlignedMul(const char * s1, const int * h1, const int * t1,
const char * s2, const int * h2, const int * t2,
char * s3, int * h3, int * t3, const int * s3Size)
{ //return 0 = no error, return 60, 61 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
*h3 = *t3 - (*t1 - *h1); //*h3 to *t3 has the same size as *h1 to *t1 in the begining.
if (tempRetVal = bigInt_chSet(s3, h3, t3, '0'))
return tempRetVal;
for (int i = *t2; i >= *h2; --i)
{
char carry = '0';
int tailAlign = *t3 - (*t2 - i); //tailAlign is moving according i move.
//s3: one char longer than s1 with '0' at first, no carry will occur during calculation
if (tempRetVal = bigInt_chSetBeforeHead(s3, h3, t3, s3Size, '0'))
return tempRetVal;
char multiplier = s2[i];
while (multiplier != '0')
{
if (tempRetVal = bigInt_strTailAlignedAdd(s3, h3, &tailAlign,
s1, h1, t1, &carry))
return tempRetVal;
if (carry == '1') // s3 is one char longer than s1, carry should be '0' always.
return 61; //Error: something wrong.
if (tempRetVal = bigInt_chDec(&multiplier))
return tempRetVal;
}
}
if (tempRetVal = bigInt_headTailValidate(*h3, *t3))//double check only.
return tempRetVal; //Error: wrong parameter.
return 0;
}
int bigInt_strMul(const char * str1, const char * str2, int * resultInBuffer,
char * buffer, const int * bufferSize)
{ //return 0 = no error, return 65 = error!
int tempRetVal;
int pn1, iq1, dq1, dp1;
if (tempRetVal = bigInt_parse(str1, &pn1, &iq1, &dq1, &dp1))
return tempRetVal;
int pn2, iq2, dq2, dp2;
if (tempRetVal = bigInt_parse(str2, &pn2, &iq2, &dq2, &dp2))
return tempRetVal;
//align the size of str1 and str2
//int aligned_i_size = (iq1 > iq2) ? iq1 : iq2; //no need for mul operation
//int aligned_d_size = (dq1 > dq2) ? dq1 : dq2; //no need for mul operation
const int safeSpaceBeforeHead = 4;
//extraSpaceInFront is required when you inserting 'carry', '.' or '-'
const int safeSpaceAfterTail = 4;
//extraSpaceAtRear is required when you inserting '.' or '\0'
//copy str1 to a position close to the end of the buffer,
//digit chars only, and name as s1.
char * s1 = buffer;
int s1Size = *bufferSize;
int h1, t1;
const char * s1Position = "end of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str1, iq1, dq1, dp1,
iq1, dq1, safeSpaceBeforeHead, safeSpaceAfterTail,
s1, s1Size, &h1, &t1, s1Position))
return tempRetVal;
//copy str2 to a position close to the start of the buffer,
//digit chars only, and name as s2.
char * s2 = buffer;
int s2Size = *bufferSize;
int h2, t2;
const char * s2Position = "start of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str2, iq2, dq2, dp2,
iq2, dq2, safeSpaceBeforeHead, safeSpaceAfterTail,
s2, s2Size, &h2, &t2, s2Position))
return tempRetVal;
//check free space in buffer
int freeSpaceInBuffer = *bufferSize - (t1 - h1 + 1) - (t2 - h2 + 1)
- safeSpaceBeforeHead * 2 - safeSpaceAfterTail * 2;
if (freeSpaceInBuffer < (t1 - h1 + 1))
return 46; //Error: not enough bufferSize
//multiply them: s1 is multiplicand, s2 is multiplier,
//to save bufferSize, s2 may destroyed during multiplying.
//range of s3 covered the range of s2
char * s3 = buffer;
int s3Size = *bufferSize;
int h3;
int t3 = h1 - 1 - safeSpaceBeforeHead; //t3 position is ahead of h1
int pn3 = pn1 * pn2;
if (tempRetVal = bigInt_strTailAlignedMul(s1, &h1, &t1,
s2, &h2, &t2, s3, &h3, &t3, &s3Size))
return tempRetVal;
//make a readable s3, read friendly for human.
int dq3 = dq1 + dq2;
if (tempRetVal = bigInt_makeFinishStr(s3, &s3Size,
&h3, &t3, &dq3, &pn3))
return tempRetVal;
//calc result index in buffer
*resultInBuffer = (int)(s3 - buffer + h3);
return 0;
}
int bigInt_mul(const char * s1, const char * s2, int * resultInBuffer,
char * buffer, const int * bufferSize)
{ //return 0 = no error.
int tempRetVal;
if (tempRetVal = bigInt_strMul(s1, s2, resultInBuffer,
buffer, bufferSize))
return tempRetVal;
return 0;
}
int bigInt_strTailAlignedDiv(char * s1, int * h1, int * t1,
char * s2, int * h2, int * t2,
char * s3, int * h3, int * t3, const int * s3Size)
{ //return 0 = no error, return 70, 71, 72, 73 = error!
int tempRetVal;
if (tempRetVal = bigInt_headTailValidate(*h1, *t1))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_headTailValidate(*h2, *t2))
return tempRetVal; //Error: wrong parameter.
if (tempRetVal = bigInt_findNewHead(s2, h2, t2))
return tempRetVal;
char isDivisorZero = 'F';
if (tempRetVal = bigInt_isZero(s2, h2, t2, &isDivisorZero))
return tempRetVal;
if (isDivisorZero == 'T')
return 70; //Error: it's not allowed: divisor == 0
if (*t1 - *h1 < *t2 - *h2)
return 72; //Error: dividend length less than divisor length is not allowed.
int quotientWritePosition = *h3; //Quotient will write here.
*t3 = *h3; //*t3 initialized to *h3, *t3 will increase while you write data.
for (int t1Align = *h1 + (*t2 - *h2) + 1; t1Align <= *t1; ++t1Align)
{ //t1Align - *h1 = *t2 - *h2 + 1, dividend is always one char longer than divisor.
char quotient = '0';
char borrow = '0';
if (tempRetVal = bigInt_strTailAlignedSubTry(s1, h1, &t1Align,
s2, h2, t2, &borrow))
return tempRetVal;
while (borrow == '0')
{
if (tempRetVal = bigInt_strTailAlignedSub(s1, h1, &t1Align,
s2, h2, t2, &borrow))
return tempRetVal;
if (tempRetVal = bigInt_chInc("ient))
return tempRetVal;
if (tempRetVal = bigInt_strTailAlignedSubTry(s1, h1, &t1Align,
s2, h2, t2, &borrow))
return tempRetVal;
}
if (tempRetVal = bigInt_chSequentialSetting(s3, h3, t3, s3Size,
"ientWritePosition, quotient))
return tempRetVal;
if (s1[*h1] == '0')
++(*h1); //s1[*h1] must be '0' now.
else
return 73; //Error: Something wrong
}
return 0;
}
int bigInt_continueDecimalDiv(char * s1, int * h1, int * t1,
char * s2, int * h2, int * t2,
char * s3, int * h3, int * t3,
const int * s3Size,
const int * truncateForQuotient,
int safeSpaceBeforeHead, int safeSpaceAfterTail)
{ //return 0 = no error
int tempRetVal;
char isDividendZero = 'F';
if (tempRetVal = bigInt_isZero(s1, h1, t1, &isDividendZero))
return tempRetVal;
char isDivisorZero = 'F';
if (tempRetVal = bigInt_isZero(s2, h2, t2, &isDivisorZero))
return tempRetVal;
int spaces_between_s3_tail_and_s1_head = (int)((s1 + *h1) - (s3 + *t3) - 1);
int move_toward_the_head = spaces_between_s3_tail_and_s1_head
- safeSpaceBeforeHead;
if (*truncateForQuotient > 0 && move_toward_the_head > *truncateForQuotient)
move_toward_the_head = *truncateForQuotient;
if (isDividendZero == 'F' && isDivisorZero == 'F' && move_toward_the_head > 0)
{
//move remainder toward head in s1, then have more space to append '0' for calculate
int moveToNewH1 = *h1 - move_toward_the_head;
int moveToNewT1 = *t1 - move_toward_the_head;
if (tempRetVal = bigInt_strCopy(s1, &moveToNewH1, &moveToNewT1, s1, h1, t1))
return tempRetVal;
*h1 = moveToNewH1; //*h1 is changed.
//fill Zero after remainder.
int setZeroFrom = moveToNewT1 + 1;
if (tempRetVal = bigInt_chSet(s1, &setZeroFrom, t1, '0')) //*t1 is not changed.
return tempRetVal;
//place a dot in s3 before write decimal parts
if (tempRetVal = bigInt_chSetAfterTail(s3, h3, t3, s3Size, '.'))
return tempRetVal;
//prepare head for quotient write in s3
int decimal_h3 = *t3 + 1;
// go!
if (tempRetVal = bigInt_strTailAlignedDiv(s1, h1, t1, s2, h2, t2,
s3, &decimal_h3, t3, s3Size))
return tempRetVal;
}
return 0;
}
int bigInt_divWithTurncate(const char * str1, const char * str2,
int * quotientInBuffer, int * remainderInBuffer,
char * buffer, const int * bufferSize,
const int * truncateForQuotient)
{ //return 0 = no error, return 80 = error!
int tempRetVal;
int pn1, iq1, dq1, dp1;
if (tempRetVal = bigInt_parse(str1, &pn1, &iq1, &dq1, &dp1))
return tempRetVal;
int pn2, iq2, dq2, dp2;
if (tempRetVal = bigInt_parse(str2, &pn2, &iq2, &dq2, &dp2))
return tempRetVal;
//align the size of str1 and str2
int aligned_i_size = (iq1 > iq2) ? iq1 : iq2;
int aligned_d_size = (dq1 > dq2) ? dq1 : dq2;
const int safeSpaceBeforeHead = 4;
//extraSpaceInFront is required when you inserting 'carry', '.' or '-'
const int safeSpaceAfterTail = 4;
//extraSpaceAtRear is required when you inserting '.' or '\0'
//copy str1 to a position close to the end of the buffer,
//digit chars only, and name as s1.
char * s1 = buffer;
int s1Size = *bufferSize;
int h1, t1;
const char * s1Position = "end of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str1, iq1, dq1, dp1,
aligned_i_size, aligned_d_size, safeSpaceBeforeHead, safeSpaceAfterTail,
s1, s1Size, &h1, &t1, s1Position))
return tempRetVal;
//copy str2 to a position close to the start of the buffer,
//digit chars only, and name as s2.
char * s2 = buffer;
int s2Size = *bufferSize;
int h2, t2;
const char * s2Position = "start of the buffer";
if (tempRetVal = bigInt_copyToBufferPosition(str2, iq2, dq2, dp2,
aligned_i_size, aligned_d_size, safeSpaceBeforeHead, safeSpaceAfterTail,
s2, s2Size, &h2, &t2, s2Position))
return tempRetVal;
//check free space in buffer
int freeSpaceInBuffer = *bufferSize - (t1 - h1 + 1) - (t2 - h2 + 1)
- safeSpaceBeforeHead * 2 - safeSpaceAfterTail * 2;
if (freeSpaceInBuffer < 4)
return 46; //Error: not enough bufferSize
// s1 / s2 = s3 ... s1 (s3 is quotient, s1 is remainder.)
char * s3 = buffer;
int s3Size = *bufferSize;
int h3 = t2 + 1 + safeSpaceAfterTail; //h3 position is after t2
int t3;
int pn3 = pn1 * pn2;
if (tempRetVal = bigInt_chSetBeforeHead(s1, &h1, &t1, &s1Size, '0'))
return tempRetVal; // insert one '0' before h1 for integer div.
if (tempRetVal = bigInt_strTailAlignedDiv(s1, &h1, &t1, s2, &h2, &t2,
s3, &h3, &t3, &s3Size))
return tempRetVal;
//calc decimal part defined by truncateForQuotient
if (*truncateForQuotient != 0)
{
if (tempRetVal = bigInt_continueDecimalDiv(s1, &h1, &t1,
s2, &h2, &t2, s3, &h3, &t3, &s3Size,
truncateForQuotient, safeSpaceBeforeHead, safeSpaceAfterTail))
return tempRetVal;
}
//make a readable s1 and s3, read friendly for human.
int dq3 = 0;
if (tempRetVal = bigInt_makeFinishStr(s3, &s3Size,
&h3, &t3, &dq3, &pn3))
return tempRetVal;
if (*truncateForQuotient == 0)
{ //remainder is only usefull for integer division
dq1 = 0;
pn1 = 1;
if (tempRetVal = bigInt_makeFinishStr(s1, &s1Size,
&h1, &t1, &dq1, &pn1))
return tempRetVal;
}
//calc result index in buffer
*quotientInBuffer = (int)(s3 - buffer + h3);
*remainderInBuffer = (int)(s1 - buffer + h1);
return 0;
}
int bigInt_divInteger(const char * str1, const char * str2,
int * quotientInBuffer, int * remainderInBuffer,
char * buffer, const int * bufferSize)
{ //return 0 = no error
int tempRetVal;
int truncateForQuotient = 0;
if (tempRetVal = bigInt_divWithTurncate(str1, str2,
quotientInBuffer, remainderInBuffer,
buffer, bufferSize, &truncateForQuotient))
return tempRetVal;
return 0;
}
int bigInt_divDecimal(const char * str1, const char * str2,
int * quotientInBuffer, char * buffer,
const int * bufferSize)
{ //return 0 = no error
int tempRetVal;
int truncateForQuotient = -1; //calc until full of buffer
int remainderInBuffer = 0; //no used data but needed for function call.
if (tempRetVal = bigInt_divWithTurncate(str1, str2,
quotientInBuffer, &remainderInBuffer,
buffer, bufferSize, &truncateForQuotient))
return tempRetVal;
return 0;
}
int bigInt_divRound(const char * str1, const char * str2, int * quotientInBuffer,
char * buffer, const int * bufferSize, int round_digits)
{ //return 0 = no error
int tempRetVal;
if (round_digits < 0)
round_digits = 0;
int truncateForQuotient = round_digits + 1; //calc to round_digits + 1
int remainderInBuffer = 0; //no used data but needed for function call.
if (tempRetVal = bigInt_divWithTurncate(str1, str2,
quotientInBuffer, &remainderInBuffer,
buffer, bufferSize, &truncateForQuotient))
return tempRetVal;
if (tempRetVal = bigInt_decimalRound(buffer + *quotientInBuffer, round_digits))
return tempRetVal;
return 0;
}
int bigInt_decimalRound(char * str, int round_digits)
{ //return 0 = no error
int tempRetVal;
int pn, iq, dq, dp;
if (tempRetVal = bigInt_parse(str, &pn, &iq, &dq, &dp))
return tempRetVal;
if (0 <= round_digits && round_digits < dq)
{
int i_head;
int i_tail;
int d_head = dp + 1;
int d_tail = dp + round_digits + 1;
int strSize = (dp + dq + 1) + 1; // no use but required by fuction call
if (iq > 0)
{
i_head = dp - iq;
i_tail = dp - 1;
}
else
{//iq == 0
if (dp > 0 && str[dp - 1] == '0')
{//there's at least one '0' before dot
i_head = dp - 1;
i_tail = dp - 1;
}
else
{//dot at very first, insert one '0' before dot
int insertBeforeThisPos = dp;
if (tempRetVal = bigInt_chInsertFromTail(str, &dp, &d_tail, &strSize,
&insertBeforeThisPos, '0'))
return tempRetVal;
++dp; //notice: above function call, only d_tail updated.
d_head = dp + 1;//notice: above function call, only d_tail updated.
i_head = dp - 1;
i_tail = dp - 1;
}
}
// add 5 at d_tail
char s[2] = { '5', '\0' };
int h = 0;
int t = 0;
char carry = '0';
if (tempRetVal = bigInt_strTailAlignedAdd(str, &d_head, &d_tail,
s, &h, &t, &carry))
return tempRetVal;
if (carry == '1')
{//if there's carry from decimal parts, add it into integer parts
s[0] = '0';
if (tempRetVal = bigInt_strTailAlignedAdd(str, &i_head, &i_tail,
s, &h, &t, &carry))
return tempRetVal;
}
if (carry == '1')
{//if there's carry from integer parts, insert it before i_head
int insertBeforeThisPos = i_head;
if (tempRetVal = bigInt_chInsertFromTail(str, &i_head, &d_tail, &strSize,
&insertBeforeThisPos, carry))
return tempRetVal;
}
int endPosition;
if (round_digits == 0)
endPosition = dp; //write '\0' at dot position;
else
endPosition = d_tail; //write '\0' at d_tail
if (tempRetVal = bigInt_chSetAtPosition(str, &i_head, &d_tail, &strSize,
&endPosition, '\0'))
return tempRetVal;
//notice: if there's '0' in the end of decimal parts, '0' is kept.
}
return 0;
}
发表于 2026-2-22 16:11
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发表于 2026-2-24 14:32
