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.IOException;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) throws IOException {
        try (
            BufferedReader reader = new BufferedReader(
                new InputStreamReader(System.in))) {
            String s = reader.readLine();

            final String[] sl = s.split(" ");
            int A = Integer.parseInt(sl[0]);
            int B = Integer.parseInt(sl[1]);

            s = reader.readLine();

            boolean flg = false;

            if (s.length() == A + B + 1) {
                flg = true;
                for (int i = 0; i < A + B + 1; i++) {
                    if (A == i) {
                        if (s.charAt(i) == '-') {
                            continue;
                        } else {
                            flg = false;
                            break;
                        }
                    }

                    if (s.charAt(i) < '0' || '9' < s.charAt(i)) {
                        flg = false;
                        break;
                    }
                }
            }
            System.out.println(flg ? "Yes" : "No");
        }
    }
}