import java.util.*;
// warm-up
// Have to check the post hyphen string for digit as well.
public class Main {

	static void solve() {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt(), B = sc.nextInt(), i=A+1;
		String s = sc.next();
		boolean ok = s.charAt(A)=='-';
		if (ok) while (i<A+B+1) ok&=Character.isDigit(s.charAt(i++));
		i=0;
		if (ok) while (i<A) ok&=Character.isDigit(s.charAt(i++));
		System.out.println(ok ? "Yes" : "No");
		sc.close();		
	}

	public static void main(String args[]) {
		solve();
	}

}
/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