Convert String to Integer

Code

#include <stdio.h>
#include <stdint.h>

int custom_atoi(const char *str) {
   
    // Your logic here
    int i = 0;
    int result = 0;
    int pos_num = 0;

    if(str[0] == '-')
    {
        pos_num = -1;
        i = 1;
    }
    else if(str[0] == '+')
    {
        pos_num = 1;
        i = 1;
    }
    else
        pos_num = 1;

   

    while(str[i] != '\0')
    {

        if(pos_num < 0)
        {
             if (str[i] >= '0' && str[i] <= '9')
            {
                result = ((result * 10) + (str[i] - '0'));
            }
            else
                break;

        }
        else if (pos_num > 0)
        {
        
            if(str[i] >= '0' && str[i] <= '9')
            {
                result = (result * 10) + (str[i] - '0');
            }
            else
                break;
        }

        i++;
    }

    if(pos_num < 0)
        result = result * -1;

    return result;
}

int main() {
    char str[101];
    fgets(str, sizeof(str), stdin);

    // Remove newline
    uint8_t i = 0;
    while (str[i]) {
        if (str[i] == '\n') {
            str[i] = '\0';
            break;
        }
        i++;
    }

    printf("%d", custom_atoi(str));
    return 0;
}

Solving Approach