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

/**************************************************************
	Problem: 1075
	User: ccf
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2324 kb
****************************************************************/