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 ret = 0;
    for (int i = 0; i < 32; i+=2) {
        if (reg & (1u << i)) ret |= (1u << (i/2));
    }
    return ret;
}

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