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
    bool even = true;
    uint32_t result = 0;
    while(reg > 0){
        if(even){
            if(reg & 1U){
                result = result << 1;
                result |= 1U;
            }
        }
        even = !even;
        reg = reg >> 1;
    }
    return result;
}

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