118. 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
    uint16_t res = 0;

    for(uint8_t i=0;str[i]!='\0';i++){
        res <<= 1;
        if(str[i]=='1'){
            res |= 1;
        }

    }

    return res;
}

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

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

Initialzise a 16 bit result variable

Run a loop from 0 to end of string 

• shift the result by 1 bit
• append 1 to the lsb if current str value is 1