Convert String to Integer

Code

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

int custom_atoi(const char *str) {
    // Your logic here
    int num = 0, flag = 0;
    while (*str != '\0') {
        if (*str == '-') flag = 1;
        else if (*str == '+') flag = 0;
        else if ('0' <= *str && *str <= '9') num = 10*num + (*str - '0');
        else break;
        str++;
    }
    return (flag) ? -num : 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