Problem:
Score : 100 points

Problem Statement

In K-city, there are n streets running east-west, and m streets running north-south. Each street running east-west and each street running north-south cross each other. We will call the smallest area that is surrounded by four streets a block. How many blocks there are in K-city?

Constraints

2 ≤ n, m ≤ 100

Input

Input is given from Standard Input in the following format:

n m

Output

Print the number of blocks in K-city.

Sample Input 1

3 4

Sample Output 1

6

There are six blocks, as shown below:

Sample Input 2

2 2

Sample Output 2

1

There are one block, as shown below:

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
import java.io.*;

class Main {

	void solve() {
		
		out.println(inint()-1 * inint()-1);
		
	}

	public static Scanner in = new Scanner(System.in);
	public static PrintWriter out = new PrintWriter(System.out);

	public static void main(String[] args) {
		new Main().solve();
		out.flush();
	}

	public int inint() {
		return in.nextInt();
	}

	public long inlong() {
		return in.nextLong();
	}
	
	public String instr() {
		return in.next();
	}

	public char inchar() {
		return in.next().charAt(0);
	}
	
	public int[] inintar(int num) {
		int[] a = new int[num];
		for (int i=0; i<num; i++) {
			a[i] = in.nextInt();
		}
		return a;
	}

	public char[] incharar() {
		return in.next().toCharArray();
	}

}