<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>
#define LL long long
#define db double
#define l first
#define r second
#define mk(a, b) make_pair(a, b)
#define Hzy(o) freopen(o".in", "r", stdin), freopen(o".out", "w", stdout)
using namespace std;

int read() {
	int w = 0, f = 0; char c = getchar();
	while((c < '0' || c > '9') && c != '-') c = getchar();
	if(c == '-') f = 1, c = getchar();
	while(c >= '0' && c <= '9') w = w * 10 + c - '0', c = getchar();
	return f ? -w : w;
}

int main() {
	int a;
	cin >> a;
	cout << 2 - a * a;
	return 0;
}
