22. Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    // Your code here
    uint32_t val = 0;
    while ((bool)reg){
        if ((bool)(reg & 1U))
            val = (val << 1) | 1U;
            reg >>= 2;
    }
    return val;
}

int main() {
    uint32_t reg;
    scanf("%u", &reg);
    printf("%u", extract_even_bits(reg));
    return 0;
}