<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 int long long
using namespace std;
const int M = 1010;
const int N = 1010;
const int mod = 1e9 + 7;
int INF = (int)1e8;
int dp[N][N][2];
int a[N][N];

int add(int a, int b)
{
    return (a % mod + b % mod) % mod;
}
void solve()
{
    int n;
    cin>>n;
    cout<<2-n*n<<endl;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int t = 1;
    // cin >> t;

    for (int i = 1; i <= t; i++)
    {
        // cout << "Case #" << i << ": ";
        solve();
    }
    return 0;
}