BUTTERFLY SHAPE

import java.util.Scanner;
class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    System.out.print("Enter a number in the interval 3-1000: ");
    int n = Integer.parseInt(sc.nextLine());
    //upper Part
    String stars = generateFrom("*",n-2);
    String dash = generateFrom("-",n-2);
    String row1 = stars+"\\" + " " + "/" + stars;
    String row2 = dash+"\\" + " " + "/" + dash;
    for(int i = 1; i<=n-2;i++){


        if(i % 2 == 0){
          System.out.println(row2);

        }
        else{
        System.out.println(row1);
        }
    }
    //center
    String centerSpace = generateFrom(" ",n-1);
    System.out.println(centerSpace + "@");
    //bottom Part
    String row3 = stars+"/" + " " + "\\" + stars;
    String row4 = dash+"/" + " " + "\\" + dash;
    for(int i = 1; i<=n-2;i++){


        if(i % 2 == 0){
          System.out.println(row4);

        }
        else{
        System.out.println(row3);
        }

    }
  }



  public static String generateFrom(String symbol,int numbersOfReps){
      StringBuffer builder = new StringBuffer();
      for(int i=0;i<numbersOfReps;i++){
          builder.append(symbol);
      }
      return builder.toString();
  }


}