#include <bits/stdc++.h>
using namespace std;
int main(){
int n,s=0,t;
cin>>n;
t=n;
while(t!=0)
{t=t/2;
 s++;
}
if(n-pow(2,s-1)<=pow(2,s)-n)cout<<pow(2,s-1);
	else cout<<pow(2,s);
return 0;
}

/**************************************************************
	Problem: 1075
	User: cx001
	Language: C++
	Result: Accepted
	Time:16 ms
	Memory:2324 kb
****************************************************************/