import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a=sc.nextInt(),b=sc.nextInt();
		String s=sc.next();
		int cnt=0;
		for(int i=0;i<(a+b+1);i++) {
			if(i==a) {
				if(s.charAt(i)=='-') {
					cnt++;
				}
			}else {
				if(s.substring(i,i+1).matches("[0-9]")) {
					cnt++;
				}
			}
		}
		System.out.println(cnt==s.length()?"Yes":"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