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