Convert Binary String to Integer Without strtol function or Libraries

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

uint16_t binary_to_uint(const char *str) {
    // Your logic here
    if(!str) return 0;
    uint16_t result = 0;
    for(int i = 0; str[i] != '\0'; i++)
    {
        result <<= 1;
        if(str[i] == '1')
            result |= 1;
    }

    return result;
}

int main() {
    char bin[20];
    scanf("%s", bin);

    printf("%u", binary_to_uint(bin));
    return 0;
}