Java program to print a cross star pattern

Java program to print a cross star pattern:

In this post, we will learn how to print a cross star pattern in Java. It will take the value of height of the pattern and it will print the pattern using star or *.

Before we move to the program, let’s learn to write down the algorithm.

Algorithm to print a cross star pattern:

Suppose we are printing the below cross star pattern:

*     *
 *   * 
  * *  
   *   
  * *  
 *   * 
*     *

Let’s replace the blank spaces with #:

*#####*
#*###*#
##*#*##
###*###
##*#*##
#*###*#
*#####*

This is the same algorithm. We need to replace the # characters with blank space.

Suppose, i represents the current row and j represents the current column.

For i = 1, * are printed at j = 1 and j = 7
For i = 2, * are printed at j = 2 and j = 6
For i = 3, * are printed at j = 3 and j = 5
For i = 4, * are printed at j = 4
For i = 5, * are printed at j = 5 and j = 3 etc.

As you can see here, * are printed if: - i and j are equal - i + j is equal to height + 1, height is 7 here

So, instead of printing #, we have to print a blank space.

import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int height;

        System.out.println("Enter the height: ");
        height = sc.nextInt();

        for (int i = 1; i < height + 1; i++) {
            for (int j = 1; j < height + 1; j++) {
                if (i == j || i + j == height + 1) {
                    System.out.print("*");
                } else {
                    System.out.print(" ");
                }
            }
            System.out.println();
        }
    }
}

It will print output as like below:

Enter the height: 
7
*     *
 *   * 
  * *  
   *   
  * *  
 *   * 
*     *

Enter the height: 
9
*       *
 *     * 
  *   *  
   * *   
    *    
   * *   
  *   *  
 *     * 
*       *

Note that, for even value of height, it will print different types of patterns i.e. both lines will not cross at the center:

Enter the height: 
10
*        *
 *      * 
  *    *  
   *  *   
    **    
    **    
   *  *   
  *    *  
 *      * 
*        *

CodeVsColor

Java program to print a cross star pattern

Java program to print a cross star pattern:

Algorithm to print a cross star pattern:

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