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>
#include <string.h>

int main(int argc, char **argv) {
  int a, b, i, len, position, count;
  char s[10];

  while (scanf("%d %d\n%s", &a, &b, s) != EOF) {
    count = 0;
    len = strlen(s);

    if (a + b + 1 != len) {
      puts("No");
      continue;
    }

    for (i = 0; i < len; i++) {
      if (s[i] == '-') {
        count++;
        position = i;
      }
    }
    if (count != 1 || position != a) {
      puts("No");
    } else {
      puts("Yes");
    }
  }

  return 0;
}