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();
      	Boolean ans = false;
		
   	       	
      for (int i =0; i<A+B+1; i++){
          if(i != A){
          if(S.charAt(i)>='0' && S.charAt(i)<='9' &&S.charAt(A) == '-'){
          	ans = true;
          }
          } 
       }
      	
      if(ans == true){
      System.out.println("Yes");
      }
      else{
       System.out.println("No");
      }
   }  	
}