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 a,b,i,l,flag=1;
    char s[20];
    scanf("%d %d",&a,&b);
    getchar();
    gets(s);
    l=strlen(s);
    if((a+b+1)!=l)
        printf("No\n");
    else
    {
        for(i=0;i<l;i++)
        {
            if(i!=a)
            {
                if(s[i]<'0'||s[i]>'9')
                {
                    flag=0;
                    break;
                }
            }
            else
            {
                if(s[i]!='-')
                {
                        flag=0;
                }

            }
        }
        if(flag==1)
            printf("Yes\n");
        else
            printf("No\n");
    }
    return 0;
}