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;

int main() {
	int  a,b;
	string s;
	cin >> a >> b;
	cin >> s;

	if (s.length() != a+b+1) {
		cout << "No" << endl;
		return 0;
	}
	for (int i=0; i<a; i++) {
		if ((s[i] < '0') || ('9' < s[i])) {
			cout << "No" << endl;
			return 0;
		}
	}
	if (s[a] != '-') {
		cout << "No" << endl;
		return 0;
	}
	for (int i=a+1; i<a+b+1; i++) {
		if ((s[i] < '0') || ('9' < s[i])) {
			cout << "No" << endl;
			return 0;
		}
	}
	cout << "Yes" << endl;
	
	return 0;
}