Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
    uint32_t n=0;
for(int i=0;i<31;i=i+2){
    if(reg&(1<<i)){n|=(1<<(i/2));}
    else{ n&=~(1<<(i/2));}
    }   
    return n; 
}

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

Solving Approach