<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 endl '\n'
#define MAX LLONG_MAX
#define MIN LLONG_MIN
#define rep(i, a, b, inc) for(long long i = a; i < b; i += inc)
#define REP(i, n) rep(i, 0, n, 1)

typedef unsigned long long ULL;
typedef long long ll;
typedef long double ld;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    ll n;
    cin>>n;
    cout<<2-(n*n)<<endl;
    return 0;
}
