Yep (cuz i sat in that room, too)... over and over, same questions, like they all read the same book. Thing is they aren't doing that stuff day to day.... and the heavy heavy emphasis on "performance" is a little funny. These aren't space ships they're controlling, just transactions.

atoi: #include #include #include int main() { const char* s = "12345"; int sum = 0; int len = strlen(s); int multiplier = pow(10, len - 1); for (int i = 0;i < len;i++) { sum += (s[i] - '0') * multiplier; multiplier = multiplier / 10; } printf("%u\n", sum); }

int atoi(const char* s) { int sum = 0; for (char* x = s; x != ']0'; ++x) { sum = sum*10 + *x - '0'; } return sum; }

typo: for (char* x = s; *x != '\0'; ++x) {