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();
        sc.nextLine();
        String c = sc.nextLine();

        int flag = 0;
        if(c.charAt(a) != '-'){
            flag++;
        }

        String d = c.substring(0,a);
        String e = c.substring(a+1,c.length());
        if(a != d.length() || b != e.length()){
            flag++;
            System.out.println(a);
            System.out.println(d.length());
            System.out.println(b);
            System.out.println(e.length());
        }
        int count =0;
        for(char x: c.toCharArray()){
            if(x == '-'){
                count++;
            }
        }
        if(count != 1){
            flag++;
        }
        if(flag == 0){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
}