<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
// Problem: C. Fibonacci Words
// Contest: Codeforces - April Fools Day Contest 2021
// URL: https://codeforces.com/contest/1505/problem/C
// Memory Limit: 256 MB
// Time Limit: 1000 ms
// 
// Powered by CP Editor (https://cpeditor.org)

#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define int long long
#define all(v) v.begin(),v.end()
#define mod 1000000007 
#define N 200010
#define inf LLONG_MAX
#define pb(x) push_back(x)
 
signed main()
{
    fast
    int n;
    cin>>n;
    int ans=2-(n*n);
    cout<<ans;
}