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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define lvector vector<ll> 
#define rep(i,n) for(ll (i)=0; i<(n); ++(i))
#define print(a) cout << (a) << endl

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  ll a,b;cin>>a>>b;
  string s;cin>>s;
  ll c;
  bool isok=true;
  if(s[a]!='-') isok=false;
  else {
    rep(i,a) {
      c=s[i]-'0';
      isok=(0<=c&&c<=9);
      if(!isok) break;
    }
    if(isok) {
      rep(i,b) {
        c=s[a+1+i]-'0';
        isok=(0<=c&&c<=9);
        if(!isok) break;
      }
    }
  }
  if(isok) puts("Yes");else puts("No");
  return 0;
}