22. Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    uint8_t itr = 0;
    uint32_t result = 0;
    while (itr < 16) {
        result |= (((1 << (itr*2) ) & reg) >> itr);
        itr++;
    }
    return result;
}

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

This program extracts all even-positioned bits (positions 0, 2, 4, ..., 30) from a 32-bit unsigned integer and packs them into a new integer, forming a sequence. Each extracted bit is placed in consecutive positions (0, 1, 2, ...) in the result, effectively compressing the even bits into a compact form. The main function reads an input number, calls the extraction function, and prints the result. The corrected logic ensures each even bit is properly isolated and packed.