Extract Even Bits Only from 32-bit Register

Code

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

uint16_t speed = 0;

uint32_t extract_even_bits(uint32_t reg) {
    // Your code here
    uint16_t speed;
    for (int i=0;i<16;i++){
        uint16_t bit = (reg >> (2 * i)) & 1U;  
        speed |= (bit << i);     }
    return speed;
}

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

Solving Approach