Snuke has N integers: 1,2,\ldots,N. He will choose K of them and give those to Takahashi.

How many ways are there to choose K consecutive integers?

Constraints

* All values in input are integers.
* 1 \leq K \leq N \leq 50

Input

Input is given from Standard Input in the following format:


N K


Output

Print the answer.

Examples

Input

3 2


Output

2


Input

13 3


Output

11
import java.util.Scanner;

/**
 * 1,2,...,Nの整数からK個選ぶ方法は何通り？
 *
 * @author uumee
 *
 */
public class Main {

    /** main */
    public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);
	System.out.println(sc.nextInt() - (sc.nextInt() - 1));
	//sc.close();
    }

}
