<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     ll              long long
#define     mp              make_pair
#define     rep(i,a,b)      for( i=a;i<b;++i)
#define     repr(i,a,b)     for( i=a;i>=b;i--)
#define     up              upper_bound
#define     lb              lower_bound
#define     t()             int test;cin>>test;while(test--)
#define     IOS             ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

#define TRACE
#ifdef TRACE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
    template <typename Arg1>
    void __f(const char* name, Arg1&& arg1){
        cout << name << " : " << arg1 << endl;
        //use cerr if u want to display at the bottom
    }
    template <typename Arg1, typename... Args>
    void __f(const char* names, Arg1&& arg1, Args&&... args){
        const char* comma = strchr(names + 1, ','); cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
    }
#else
#define trace(...)
#endif
 
int main()
{  
    #ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif
    IOS;
   	ll n;
   	cin >> n;
   	cout << 2 - n*n << "\n";
   	return 0;
}