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
    int len=0;
    while(str[len]!='\0'){
        len++;
    }
    int result=0;
    int k=0;
    for(int j=0;j<len;j++){
    k=(str[j]=='0')?0:1;
    result=result+k*(1<<(len-j-1));
    }
    return result;
}

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

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