C - Adding the numbers in 2 strings together if a different length -
if had 2 strings: a = "1234" b = "4321" i add 2 numbers this: for(i=0; i<width-1; i++){ sum = (a[width-2-i]-48) + (b[width-2-i]-48) + carry; carry = 0; if(sum > 9){ carry = 1; sum-=10; } answer[i] = sum+48; } if(carry) answer[i++] = carry+48; answer[i]= 0; and reverse (width equal strlen(a)). how same thing if following? a = "12345" b = "4321" would need reallocate memory? or what? (btw - the problem i'm trying solve using many numbers 50 digits, strtoul or strtoull out of question understand. here's code far .) int getcharval(const char *s, int idx) { if (idx < strlen(s)) return s[strlen(s) - idx - 1] - 48; return 0; } void add() { const char *a = "1234"; const char *b = "13210"; char answer[256]; int i, wa=strlen(a), wb=strlen(b), width, sum, carry; width = wa > wb ? wa : wb; for(i=0; i<width; ...
