#include <stdio.h>
#include <stdint.h>
uint32_t extract_even_bits(uint32_t reg) {
// Your code here
uint32_t res = 0;
int f = 0;
for(int z= 0;z<32; z+=2){
if(reg&(1<<z)){
res |= (1<<f);
}
f++;
}
return res;
}
int main() {
uint32_t reg;
scanf("%u", ®);
printf("%u", extract_even_bits(reg));
return 0;
}