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();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	}
} import java.util.Scanner; Scanner java.util 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();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a=sc.nextInt(),b=sc.nextInt();
		String s = sc.next();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	} main {
		Scanner sc = new Scanner(System.in);
		int a=sc.nextInt(),b=sc.nextInt();
		String s = sc.next();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a=sc.nextInt() a sc.nextInt() sc.nextInt sc b=sc.nextInt(); b sc.nextInt() sc.nextInt sc String s = sc.next(); s sc.next() sc.next sc if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		} s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-") s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-") s.length() == a+b+1 s.length() s.length s a+b+1 a+b+1 a b 1 s.indexOf("-") == a s.indexOf("-") s.indexOf s "-" a s.indexOf("-") == s.lastIndexOf("-") s.indexOf("-") s.indexOf s "-" s.lastIndexOf("-") s.lastIndexOf s "-" {
			System.out.println("Yes");
			return;
		} System.out.println("Yes") System.out.println System.out System System.out "Yes" return; System.out.println("No") System.out.println System.out System System.out "No" String[] args args 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();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	}
} 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();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	}
} Main
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();
		if(s.length() == a+b+1 &&
			s.indexOf("-") == a &&
			s.indexOf("-") == s.lastIndexOf("-")) {
			System.out.println("Yes");
			return;
		}
		System.out.println("No");
	}
}
