import java.util.Scanner;

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

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