Extract Even Bits Only from 32-bit Register

Code

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

uint32_t extract_even_bits(uint32_t reg) {
    // Your code here
    uint32_t ret_val = 0;
    uint8_t idx = 0;
    while (reg)
    {
        
        ret_val |= ((reg & 1) << idx);
        reg = reg >> 2;
        idx++;
    }

    return ret_val;
}

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

Solving Approach