Problem:
Score : 200 points

Problem Statement

The postal code in Atcoder Kingdom is A+B+1 characters long, its (A+1)-th character is a hyphen -, and the other characters are digits from 0 through 9.

You are given a string S. Determine whether it follows the postal code format in Atcoder Kingdom.

Constraints

1≤A,B≤5

|S|=A+B+1

S consists of - and digits from 0 through 9.

Input

Input is given from Standard Input in the following format:

A B
S

Output

Print Yes if S follows the postal code format in AtCoder Kingdom; print No otherwise.

Sample Input 1

3 4
269-6650

Sample Output 1

Yes

The (A+1)-th character of S is -, and the other characters are digits from 0 through 9, so it follows the format.

Sample Input 2

1 1
---

Sample Output 2

No

S contains unnecessary -s other than the (A+1)-th character, so it does not follow the format.

Sample Input 3

1 2
7444

Sample Output 3

No

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		String s = sc.next();
		char[] cs = s.toCharArray();
		int cnt = 0;

		if (String.valueOf(cs[a]).equals("-")) {
			for (int i = 0; i < a; i++) {
				if (Character.isDigit(cs[i])) {
					cnt++;
				}
			}
			for (int i = (a + 1); i <= (a + b); i++) {
				if (Character.isDigit(cs[i])) {
					cnt++;
				}
			}
			if (cnt == (a + b)) {
				System.out.println("Yes");
			} else {
				System.out.println("No");
			}
		} else {
			System.out.println("No");
		}

		sc.close();
	}

}