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.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.stream.Stream;
public class Main {
	public static void main(String[] args) {
		try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
				PrintWriter pw = new PrintWriter(System.out);) {
			int[] AB = Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
			String[] S = br.readLine().split("-");
			if (S.length == AB.length && AB[0] - AB[1] == S[0].length() - S[1].length()) {
				pw.println("Yes");
			} else {
				pw.println("No");
			}
			pw.flush();
		} catch (Exception e) {
		}
	}
}