Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    uint16_t regi = 0;

    for (int i = 0; i < 16; i++) {
        if (reg & (1u << (i * 2))) {
            regi |= (1u << i);  
        }
    }

    return regi;
}

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

Solving Approach