<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 rep(i, a, b) for(int i = a; i < (b); ++i)
# define trav(a, x) for(auto& a : x)
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int a;
    cin >> a;
    cout << 2-a*a << endl;
    return 0;
}
