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 res = 0;
    uint32_t value;

    for(int i = 0; i < 32; i=i+2)
    {
        value = (reg >> i) & 0x01;
        res &= ~(0x01 << i/2);            
        res |= (((value) & 0x01) << i/2); 
    }
    return res;
}

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