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 i ;
    uint16_t val ;
    /*
    for(i = 0 ; i < 32 ; i += 2){
    if((reg >> i) & 1){
    val |= (1 << out_pos) ;
    out_pos++ ;
    }
    return val ;
    }
    */
    for(i = 0 ; i < 32 ; i += 2){
        val += (((reg >> i) & 1) << (i/2)) ;
    }
    return val ;
}

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