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();
        try{
            Integer.parseInt(s.substring(0,a));
            if(s.charAt(a)!='-')throw new Exception();
            Integer.parseInt(s.substring(a+1));
            System.out.println("Yes");
        }catch(Exception e){
            System.out.println("No");
        }
    }

}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz