15. Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    uint32_t result = 0;
    int out_pos = 0;

    for (int i = 0; i < 32; i += 2) {
        // If bit i is set, place it in the result at the next position
        if ((reg >> i) & 1) {
            result |= (1U << out_pos);
        }
        out_pos++;
    }

    return result;
}

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