<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>
#define IOS ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
#define nline "\n"
using ll=long long;
using namespace std;
int main(){
    IOS
    int t = 1;
    //cin>>t;
    while(t--){
        int num;
        cin >> num;
        cout << 2 - num * num << nline;
    }
    return 0;
}