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.nextLine();
        String[] SS=S.split("-",0);
        if(SS[0].length()==A&&SS[1].length()==B){
            System.out.println("Yes");

        }else{
            System.out.println("No");
        }

        
        


    }
}
