<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
//This code is written by प्रविण शंखपाळ 

//package wizard;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Collections;
import java.util.Comparator;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.Stack;
import java.util.Queue;
import java.util.PriorityQueue;
import java.util.List;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.TreeSet;
import java.util.Map;
import java.util.HashMap;
import java.util.Scanner;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.Vector;

public class Luna_Lovegood {

	public static void main(String[] args) {

		try {

			FastReader fr = new FastReader();
			BufferedWriter output = new BufferedWriter(new OutputStreamWriter(System.out));

			int a = fr.nextInt();

			System.out.println(2 - a * a);

		} catch (Exception e) {
			return;
		}
	}

	static class Pair implements Comparable<Pair> {
		int a, b;

		Pair(int a, int b) {
			this.a = a;
			this.b = b;
		}

		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			if (this.a != o.a)
				return Integer.compare(this.a, o.a);
			else
				return Integer.compare(this.b, o.b);
			// return 0;
		}

		public boolean equals(Object o) {
			if (o instanceof Pair) {
				Pair p = (Pair) o;
				return p.a == a && p.b == b;
			}
			return false;
		}

	}

	static int binarySearch(int arr[], int first, int last, int key) {
		int mid = (first + last) / 2;
		while (first <= last) {
			if (arr[mid] < key) {
				first = mid + 1;
			} else if (arr[mid] == key) {
				return mid;
			} else {
				last = mid - 1;
			}
			mid = (first + last) / 2;
		}
		return -1;
	}

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}
}
