<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 <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <cmath>
#include <stack>
#include <iomanip>
#include <bitset>
#include <set>
#include <map>
 
#define szybcior ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
 
using namespace std;
typedef long long ll;
typedef long double ld;
typedef  pair<int,int> iPair;
typedef  pair<ll,ll> llPair;
const ll inf = 10e7;
const ll ile = 500002;
ll a;
 
int main()
{
    szybcior;
    cin >> a;
    cout << 2 - a * a;
    return 0;
}