#include <bits/stdc++.h>
using namespace std;

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);

	int n; cin >> n;
	int mi = n - 100;
	int mx = n + 100;
	if(mi % 2 == 0) cout << mi << endl;
	else cout << mi + 1 << endl;                        
	return 0;
}