22. Extract Even Bits Only from 32-bit Register

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

uint32_t extract_even_bits(uint32_t reg) {
   uint32_t mask = 0x5555;
   uint32_t even_bits = 0x0000;
   uint32_t extract = reg & mask;
   int j=0;
   for(int i=0;i<32;i+=2)
   {
      uint32_t temp = (reg>>i) & (1u);
      even_bits |= (temp << j);
      j++;
   }
   return even_bits;    
}

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