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 output = 0;
    int j = 0;
    for (int i = 0; i < 32; i += 2) {
        uint32_t bit = (reg >> i) & 1;
        output |= (bit << j);
        j++;
    }
    return output;
}

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