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 C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

class MainClass
{
    static void Main()
    {
        var ab = Console.ReadLine().Split().Select(int.Parse).ToArray();
        int a = ab[0], b = ab[1];
        string S = Console.ReadLine();
        if (S.Length == a + b + 1)
        {
            if(S[a]=='-'&&int.TryParse(S.Substring(0,a),out int n)&&int.TryParse(S.Substring(a+1),out int m))
            {
                Console.WriteLine("Yes");
                return;
            }
        }
        Console.WriteLine("No");
    }
}