import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	} main {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a a b; b String s; s a = sc.nextInt() a sc.nextInt() sc.nextInt sc b = sc.nextInt() b sc.nextInt() sc.nextInt sc s = sc.next() s sc.next() sc.next sc for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		} int i = 0; int i = 0; i 0 i < a + b + 1 i a + b + 1 a + b + 1 a b 1 i++ i++ i {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		} {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		} if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			} i != a && s.charAt(i) == '-' i != a i a s.charAt(i) == '-' s.charAt(i) s.charAt s i '-' {
				System.out.print("No");
				return;
			} System.out.print("No") System.out.print System.out System System.out "No" return; if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			} i == a && s.charAt(i) != '-' i == a i a s.charAt(i) != '-' s.charAt(i) s.charAt s i '-' {
				System.out.print("No");
				return;
			} System.out.print("No") System.out.print System.out System System.out "No" return; System.out.print("Yes") System.out.print System.out System System.out "Yes" String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	}
} Main
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a, b;
		String s;
		a = sc.nextInt();
		b = sc.nextInt();
		s = sc.next();

		for (int i = 0; i < a + b + 1; i++) {
			if(i != a && s.charAt(i) == '-') {
				System.out.print("No");
				return;
			} else if(i == a && s.charAt(i) != '-') {
				System.out.print("No");
				return;
			}
		}

		System.out.print("Yes");
	}
}