Convert Binary String to Integer Without strtol function or Libraries

Code

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

uint16_t binary_to_uint(const char *str) {
    // Your logic here
    int n=0;
    uint16_t sum =0;
    while(*(str+n) != '\0')
    {
        n++;
    }
    int j=0;
    for(int i=n-1;i>=0;i--)
    {
        sum += (*(str+i) - '0') * pow(2,j);
        j++;
    }
    return sum;
}

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

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

Solving Approach