Loop Exercise: Printing a tree on console using for loops (Stuck on details)

Question

This is an exercise for uni I've been working on but I've been stuck on just one last little problem with the output and I just can't find out why.

Goal: User inputs height of tree. It gets printed in the following format:

E.g height 4

4|  *  |5=2+1+2   (width = 2 spaces+ 1 char + 2 spaces)
3| *** |5=1+3+1
2|*****|5=0+5+0
1| *** |5=1+3+1

Note: The Root is always 3 characters long and should be 1/4th of the height (round off)

Here's my problem: It works fine for every input <8. First I was looking at the wrong place because I feel like it had something to do with the number itself. But 8 is the first height where the root is 2 lines instead of one. (8 * 1/4 = 2) Regardless I could not find a solution (not even a bad one).

I hope my code is readable, I tried to remove everything unnecessary and change the variables to English ones.

My assignment is basically done, it's just this minor detail I cant get a grip on. It's not like I'm asking anyone to do my homework for me; there's on learning in that I agree.

---

Here's my output for height (works fine)

 7|     *     |11=5+1+5
 6|    ***    |11=4+3+4
 5|   *****   |11=3+5+3
 4|  *******  |11=2+7+2
 3| ********* |11=1+9+1
 2|***********|11=0+11+0
 1|    ***    |11=4+3+4

For anything bigger than 8, e.G 8 I get the following problem in the Root Lines of the tree:

 8|      *      |11=5+1+5
 7|     ***     |11=4+3+4
 6|    *****    |11=3+5+3
 5|   *******   |11=2+7+2
 4|  *********  |11=1+9+1
 3| *********** |11=0+11+0
 2|    ***    |11=4+3+4              <--- amount of spaces is still correct but my formating got butchered as you can see, line 3 no longer touches the edges (|), its shifted 
 1|    ***    |11=4+3+4              

Here's my code:

import java.util.Scanner;

public class SchleifenTestat
{
    public static void main(String[] args)
    {
        Scanner read = new Scanner(System.in);

          System.out.print("Enter height:");
          int height= read.nextInt();

          int heightOutput= height;
          int root = (int)(height*0.25F);  
          int width= ((height- root) * 2) -1; //Amount of chars in the widest tree line
          int spaces = (width- 1); //Amount of spaces line 1
          int charCount = 1;
          int tree = (height- root); 



          for(int i = 0; i < tree; i++)   
          {
              if(heightOutput<10)
              {
                  System.out.print(" ");  //To stay in format with heights <9

              }

                System.out.print(heightOutput+"|");
                heightOutput--;

                      for(int j=0; j<= height- i -3 ;j++)
                      {
                          System.out.print(" ");

                      }
                      for(int k=0; k < i*2 + 1; k++ )
                      {
                        System.out.print("*");

                      }
                      for(int j=0; j<=(height- i - 3);j++)  //5 = 2 + * + 2
                      {
                          System.out.print(" ");
                      }

                      System.out.print("|" + width+ "=" + (spaces/2) + "+" + charCount+ "+" + (spaces/2));
                      System.out.println();

                      charCount+=2;
                      spaces -=2;
          }

          for(int i = heightOutput; heightOutput> 0; heightOutput--)
          {
              System.out.print(" " + heightOutput + "|");

              for(int j = 0; j<((width-3)/2);j++)
              {
                  System.out.print(" ");          //Spaces left side 
              }

              System.out.print("***");           //Root

              for(int j = 0; j<((width-3)/2);j++)
              {
                  System.out.print(" ");          //Spaces right side 
              }

              System.out.print("|" + width+ "=" + ((width-3 )/2) + "+" + "3" + "+" + ((width- 3)/2));
              System.out.println("");

          }

    }
}

Answer 1

There is a lot going on here. I took the liberty of refactoring your program a bit/lot. Each time you use the same expression multiple times like (width-3)/2 think about what this value means to you and pass it into a variable with a name. Same with Lines you use multiple times, like your left and right borders and so on. If you do this your program should become less numbers and more semantic constructs with meaning you can understand. This is where I arrived at and voila it works. :D

import java.util.Scanner;

public class SchleifenTestat
{
    public static void main(String[] args)
    {
        Scanner read = new Scanner(System.in);

          System.out.print("Enter height:");
          int height= read.nextInt();

          int heightOutput= height;
          int root = (int)(height*0.25F);  
          int width= ((height- root) * 2) -1; //Amount of chars in the widest tree line
          int spaces = (width- 1); //Amount of spaces line 1
          int spacesOneSide = spaces / 2;
          int charCount = 1;
          int tree = (height- root); 



          for(int i = 0; i < tree; i++)   
          {
              printLeftBorder(heightOutput);
              heightOutput--;

              printLine(spacesOneSide, charCount);

              printRightBorder(width, charCount, spacesOneSide);

              charCount+=2;
              spacesOneSide--;
          }

          while(heightOutput> 0)
          {
              int freeSpacesEachSide = ((width-3) / 2);
              printLeftBorder(heightOutput);

              printLine(freeSpacesEachSide, 3);

              printRightBorder(width, 3, freeSpacesEachSide);
              heightOutput--;
          }

          read.close();
    }

    private static void printRightBorder(int width, int charCount, int spacesOneSide)
    {
        System.out.print("|" + width+ "=" + spacesOneSide + "+" + charCount+ "+" + spacesOneSide);
        System.out.println("");
    }

    private static void printLeftBorder(int number)
    {
        if(number<10)
        {
            System.out.print(" ");  //To stay in format with heights <9
        }
        System.out.print(number+"|");       
    }

    private static void printLine(int spacesOneSide, int charCount)
    {
        printString(" ", spacesOneSide);
        printString("*", charCount);
        printString(" ", spacesOneSide);
    }

    private static void printString(String string, int times)
    {
        for(int i = 0; i < times; i++)
        {
            System.out.print(string);
        }
    }
}

Oh and close your scanners. If you have any questions regard my answer, feel free to ask, slow day :)

Happy Coding