<image> <image>

*The two images are equivalent, feel free to use either one.

Input

The input contains a single integer a (-100 ≤ a ≤ 100).

Output

Output the result – an integer number.

Example

Input


1


Output


1
#define _CRT_SECURE_NO_WARNINGS
#define fast ios::sync_with_stdio(false); cin.tie(0)
#define foru(i, k, n) for (int i = k; i < n; i++)
#define ford(i, k, n) for (int i = k; i >= n; i--)
#define pb push_back
#define mp make_pair

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <numeric>
#include <queue>
#include <bitset>

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;



int main() {
	fast;
	int a;
	cin>>a;
	cout<<2-a*a<<'\n';
	return 0;
}