#include <stdio.h>
#include <stdint.h>
uint32_t extract_even_bits(uint32_t reg) {
int a = 0,b=0,c=0;
for(int i=0;i<32;i++)
{
if(i%2==0)
{
if((1<<i)®)
{
b |= 1<<c;
c++;
//a |= ((b)|1);
}
else{
b |= 0<<c;
c++;
//a |= ((b)|0);
}
}
}
return b;
}
int main() {
uint32_t reg;
scanf("%u", ®);
printf("%u", extract_even_bits(reg));
return 0;
}