Convert String to Integer

Code

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

int custom_atoi(const char *str) {
    int num=0,i=0;
    if(str[0]=='+' || str[0]=='-'){
        i=1;
    }
    for(;str[i];i++){
        if(str[i]>='0' && str[i]<='9'){
            num*=10;
            num+=str[i]-'0';
        }
        else{
            break;
        }
    }
    if(str[0]=='-'){
        num=-num;
    }
    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