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
    reg = reg & (0x55555555);
    reg = reg | (reg>>1);
    reg = reg & (0x33333333);
    reg = reg | (reg>>2);
    reg = reg & (0x0F0F0F0F);
    reg = reg | (reg>>4);
    reg = reg & (0x00FF00FF);
    reg = reg | (reg>>8);
    reg = reg & (0x0000FFFF);
    return reg;
}

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