<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
// Keep it simple
#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define Br cout<<endl
#define int long long
#define fe first
#define se second
#define double long double
#define all(v) v.begin(),v.end()
#define allr(v) v.rbegin(),v.rend()
#define PT(x) cout << (x) << endl
#define last(x)  prev(x.end())
#define PP(x) cout << (x) << " "
#define PS(x) for(auto it: x)cout << it <<" "; cout << endl;
#define PTT(x) cout << (#x) << " is " << (x) << endl
#define lets_go ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
void PV(vi v) { for (int i = 0 ; i < (int)v.size() ; i++) cout << v[i] << " " ; cout << endl;}
void PVV(vii v) {for (int i = 0 ; i < (int)v.size() ; i++) cout << v[i].first << " " << v[i].second << endl;}
void PA(int v[], int n, int x = 0) { for (int i = x ; i < n + x; i++)cout << v[i] << ' ' ; cout << endl;}
void IN(int a[], int n, int x = 0) {for (int i = x; i < n + x; i++)cin >> a[i];}
inline void op() {
#ifndef ONLINE_JUDGE
   freopen("input.txt", "r", stdin);
   freopen("output.txt", "w", stdout);
#endif
}

// <=================================================================================================================================
// <=================================================================================================================================
const int M = 1e9 + 7;
const int IM = 1e18 + 37;
const int N = 5e5 + 10;


signed  main() {
   lets_go
   op();

   int n;
   cin >> n;
   PT(2 - n * n);

   return 0;
}
