Convert String to Integer

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

int custom_atoi(const char *str) {
    // Your logic here 
    int i =0; 
    int num =0 ; 
    int flag = 0; 
    if (str[0] == '-' || str[0] == '+' )
    {

        i = 1; 
    }
    while(str[i] != '\0')
    {
           if (str[i] >= '0' && str[i] <= '9')
           {
                num  =  (num * 10 ) +  ( int(str[i]) - '0' );
               /// printf("%d\n" , num);
           }
           else 
           {
            break;
           }
           i ++;
    }
    if (str[0] == '-')
    {
        return 0 - 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;
}