import java.util.*;
import java.io.*;

public class Main{
	public static boolean isInteger( String input ) { //Pass in string
    	try { //Try to make the input into an integer
        	Integer.parseInt( input );
        	return true; //Return true if it works
    	}
    	catch( Exception e ) { 
        	return false; //If it doesn't work return false
    	}
	} 

	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		String s = sc.next();
		
		if(s.length() == (a + b + 1)){ 
			if(s.charAt(a) == '-'){
				String s1 = s.substring(0, a);
				String s2 = s.substring(a+1);
				if(isInteger(s1) && isInteger(s2))
					System.out.println("Yes");
				else
					System.out.println("No");
			}else{
				System.out.println("No");
			}
		}else{
			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