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.Linq;

namespace Sample
{
  class Sample
  {
    static void Main(string[] args)
    {
      
      string[] str=Console.ReadLine().Split(' ');
     int A=int.Parse(str[0]);
      int B=int.Parse(str[1]);
      string s=Console.ReadLine();
      int flg=0;
      try{
        int fw=int.Parse(s.Substring(0,A));
      }catch (Exception){
        flg=1;
      }
      if(s.Substring(A,1)!="-"){
        flg=1;
      }try{
        int le=int.Parse(s.Substring(A+1));
        if(s.Substring(A+1).Length!=B){
          flg=1;
        }
      }catch (Exception){
        flg=1;
      }
      if(flg==0){
        Console.WriteLine("Yes");
      }else{
        Console.WriteLine("No");
      }
    }
    
  }

}