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>
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define all(x) (x).begin(),(x).end()
#define INF 10000000

using namespace std;

int main(){
    int a,b;
    cin >> a >> b;
    string S;
    cin >> S;
    bool ok = true;
    rep(i,a){
        if (!(('0'<=S[i]) && (S[i]<='9'))) {
            ok = false;
        }
    }
    if (!(S[a]=='-')) {
        ok = false;
    }
    for(int i=a+1;i<=a+b;i++){
        if (!(('0'<=S[i]) && (S[i]<='9'))){ 
            ok = false;
        }
    }
    if (ok) puts("Yes");
    else puts("No");
}