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 Fortran (gfortran v4.8.4) (judge verdict: Wrong Answer)

program proB
  implicit none
  integer i,j,a,b
  character s*9,check*10

  read(*,*) a,b
  read(*,*) s

  check='0123456789'
  do i=1,a+b
     if(i==a+1) then
        if(s(i:i)=='-') then
           cycle
        else
           write(*,*) 'No'
           stop
        end if        
     else if(s(i:i)=='0' .or. s(i:i)=='1' .or. s(i:i)=='2' .or. s(i:i)=='3' &
          .or. s(i:i)=='4' .or. s(i:i)=='5' .or. s(i:i)=='6' .or. s(i:i)=='7' &
          .or. s(i:i)=='8' .or. s(i:i)=='9') then
        cycle
     else
        write(*,*) 'No'
        stop
     end if
  end do

  write(*,*) 'Yes'
  

end program proB