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 (GCC 5.4.1) (judge verdict: Accepted)

#include<stdio.h>

int main() {
	int a, b, valid_flg, i;
	char s[1000];
	scanf("%d%d%s", &a, &b, &s);
	valid_flg = 1;
	for (i = 0; s[i] != '\0'; i++) {
		if (i == a && s[i] != '-') {
			valid_flg = 0;
			break;
		} else if (i != a && s[i] == '-') {
			valid_flg = 0;
			break;
		}
	}
	printf(valid_flg ? "Yes" : "No");
	return 0;
}