Convert Binary String to Integer Without strtol function or Libraries

Code

#include <stdio.h>
#include <stdint.h>
uint16_t binary_to_uint(const char *str)
{
   uint16_t result = 0;

    for (int i = 0; str[i] != '\0'; i++) {
        result <<= 1;  // Shift left by 1
        if (str[i] == '1') {
            result |= 1;  // Add 1 if current char is '1'
        } else if (str[i] != '0') {
            // Invalid character
            return 0xFFFF;  // Optional error handling
        }
    }
    return result;
}
int main() {
    char bin[20];
    scanf("%s", bin);

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

Solving Approach