<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
#include<bits/stdc++.h>
using namespace std;
#define ll long long 
ll x[1000005];
ll s[1000006];
int main() {
	ll x;
	cin >> x;
	cout << 2-x * x;
}