22. Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    uint32_t mask = 0;
    uint32_t extracted_mask,result=0;
    for(int i=0; i<32; i+=2)
    {
        mask = mask | (1U<<i);
    }

    extracted_mask = mask & reg;
    for(int j=0; j<32; j+=2)
    {
        if ((extracted_mask >> j) & 1U)
        {
            result |= ( 1U << (j/2));
        }
    }

    return result;
}

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