import 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 str = sc.next();
    boolean test = true;

    for(int i=0; i < A; i++){
        if(Character.isDigit(str.charAt(i))){
            
        }else{
            test = false;
            break;
        }
    }
    for(int i=A+1; i < A+B+1; i++){
        if(Character.isDigit(str.charAt(i))){
            
        }else{
            test = false;
            break;
        }
    }
    if(str.matches(".*"+"-"+".*")){
         
    }else{
        test = false;
    }
    if(test){
        System.out.println("Yes");
    }else{
        System.out.println("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