Convert String to Integer

Code

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

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

    // Setting the negative flag for negative number
    if(str && str[0] == '-') neg_set = 1;

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

        if(i == 0 && (str[i] == '+' || str[i] == '-')){
            i++;
            continue;
        }

        if(!(str[i] >= '0' && str[i] <= '9')) break;

        num = num * 10 + (str[i] - '0'); 

        i++;
    }

    if(neg_set) num *= -1;

    return num;
}

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