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: Runtime Error)

#include <stdio.h>
#include <string.h>
int main(){
  int a,b,len;
  char *s;
  scanf("%d%d%s",&a,&b,*s);
  len = strlen(s);
  for(int i=0;i<a;i++){
    if(s[i]=='-'){
      printf("No");
      return 0;
    }
  }
  if(s[a]!='-'){
    printf("No");
    return 0;
  }
  for(int i=a+1;i<a+b+1;i++){
    if(s[i]=='-'){
      printf("No");
      return 0;
    }
  }
  printf("Yes");
  return 0;
}