I need a program that continually asks the user if they would like to see a triangle. If the user types "Y" or "y" it prints a triangle made out of x's with a random amount of rows (1-20). After that it continually asks for the answer y again and print another triangle with a different amount of rows until the user types any response which ends the program

this is the code that is needed to be changed so that it continually looks for the answer "Y" or "y" to proceed printing a triangle :

   import java.util.Scanner; 
   public class DrawTriangle {
       public static void main(String[] args)
   {
       Scanner sc = new Scanner(System.in);
       System.out.println("Enter the number of rows of the triangle");
       int rows = sc.nextInt();

       //iterates for the given number of rows
       for (int i = 1; i <= rows; i  ) {

           //prints the number of spaces before the x
           for (int j = rows; j >= i; j--) {
            System.out.print(" ");
          }

           //prints the number of x's in each row
           for (int j = 1; j <= i; j  ) {
            System.out.print("x ");
          }

           //prints new line for each row
           System.out.println();
    }
}

}

CodePudding user response：

This program checks if the user wants to draw a program and if the answer is yes then it will ask for the number of rows and it will repeat until the user inputs something that isn't yes

import java.util.Scanner;

public class Main {
    
    public static void main(String[] args) throws InterruptedException {
        
        Scanner scanner = new Scanner(System.in);
        System.out.println("Draw triangle?");
        String answer = scanner.nextLine();
        
        while (answer.toLowerCase().equals("yes")) {
            
            System.out.println("Enter the number of rows of the triangle");
            int rows = scanner.nextInt();

            //iterates for the given number of rows
            for (int i = 1; i <= rows; i  ) {

                //prints the number of spaces before the x
                for (int j = rows; j >= i; j--) {
                    System.out.print(" ");
                }

                //prints the number of x's in each row
                for (int j = 1; j <= i; j  ) {
                    System.out.print("x ");
                }

                //prints new line for each row
                System.out.println();
                 
            }
            
            System.out.println("Draw triangle?");
            scanner.nextLine();
            answer = scanner.nextLine();
            
        }
        
        scanner.close();
            
    }

}

CodePudding user response：

Your logic to draw the triangle is working, you should however factor that out to a separate method as you may be calling it multiple times.

To create a random number use new Random().nextInt(). And for the retries use a while loop.

import java.util.*;

public class Application {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        var rng = new Random();
        System.out.println("Do you want to draw a triangle? [y/Y]");
        var answer = sc.nextLine();
        while (answer.compareToIgnoreCase("y") == 0){
            System.out.println("Do you want to draw a triangle? [y/Y]");
            // create random int between 1 (inclusive) and 21 (exclusive)
            var rows = rng.nextInt(1, 21);
            // print the triangle
            printTriangle(rows);
            answer = sc.nextLine();
        }
        System.out.println("Exiting program");
    }

    public static void printTriangle(int rows) {
        //iterates for the given number of rows
        for (int i = 1; i <= rows; i  ) {
            //prints the number of spaces before the x
            for (int j = rows; j >= i; j--) {
                System.out.print(" ");
            }
            //prints the number of x's in each row
            for (int j = 1; j <= i; j  ) {
                System.out.print("x ");
            }
            //prints new line for each row
            System.out.println();
        }
    }
}