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 <iostream>
#include <string>
using namespace std;
int a, b;
string st;
bool w = true;
int main() {
	cin >> a >> b;
	cin >> st;
	for (int i = 0; i < a; i++) {
		if (int(st[i]) > 57 || int(st[i]) < 48) {
			w = false;
		}
	}
	if (st[a] != '-')
		w = false;
	for (int i = a + 1; i < a + b; i++) {
		if (int(st[i]) > 57 || int(st[i]) < 48)
			w = false;
	}
	if (w)
		cout << "Yes\n";
	else cout << "No\n";
}