import java.util.*;
public class Main{
	public static void main(String[] args){
    	Scanner sc = new Scanner(System.in);
      int a = sc.nextInt();
      int b = sc.nextInt();
      String s = sc.next();
      String pattern = "[0-9]{"+a+"}-[0-9]{"+b+"}";
      if( s.matches(pattern) ) System.out.println("Yes");
      else System.out.println("No");
    }
}