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

/**************************************************************
	Problem: 1075
	User: fzy001
	Language: C++
	Result: Accepted
	Time:17 ms
	Memory:2072 kb
****************************************************************/