gistfile1.txt

#include <stdio.h>

int my_atoi(const char *str)
{
        int neg = 1;
        int x = 0;
        if (*str == '-') 
        {
                neg = -1;
                *str++;
        }
        while (*str >= '0' && *str <= '9')
        {
                x *= 10;
                x += *str++ - '0';
        }
        return neg * x;
}