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 ans = 0;
    for (int i=0; i<32; i++){
        if (i%2 == 0){
            int bit = (reg >> i) & 1;
            if (i == 0){
                ans |= bit;
            } else {
                ans |= (bit << (i/2));
            }
        }
    }
    return ans;
}

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