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(void){
   int a,b,i,n;
   scanf("%d%d",&a,&b);
   char str[a+b];
   scanf("%s",str);


   for(i=0;i<a;i++)
      if((str[i]<'0')||(str[i]>'9')){printf("No\n");return 0;}

   if(str[i]!='-'){printf("No\n");return 0;}

   for(i+=1;i<a+b;i++);
      if((str[i]<'0')||(str[i]>'9')){printf("No\n");return 0;}


   printf("Yes\n");
   return 0;
}