Learn how to do Pyramid Pattern printing in Java

Board Infinity -

Introduction

One of the most common questions in Programming is pattern printing, where you're asked to print different patterns according to the input given. One such problem is Pyramid Pattern printing. In this article, we will see how we can print a pyramid pattern in Java using different iterations.

Sample Input

N = 3

Sample Output

*

* *

* * * 

Sample Input

N = 5

Sample Output

*

* *

* * *

* * * *

* * * * *

Using for loop

The following program prints the pyramid pattern using for loop:

Source Code

class HelloWorld {
   
    public static void printPyramidPattern(int N)
    {
       
        // Outer loop to handle number of rows
        for(int index1 = 0; index1 < N; index1++)
        {
            //  Inner loop to print stars
            // on an specific row
            for(int index2 = 0; index2 <= index1; index2++)
            {
                // Print stars
                System.out.print("* ");
            }
            // Next line after each row
            System.out.println();
        }
   }
  
    public static void main(String[] args) {
       
        // Initialize a variable
        int N = 5;
       
        // Display the pattern
        printPyramidPattern(N);
    }
}

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Output

Using while loop

The following program prints the pyramid pattern using a while loop:

Source Code

class HelloWorld {
   
    public static void printPyramidPattern(int N)
    {
       
        int row = 1, column = 0;
       
        // The while loop
        // to loop and execute the statements
        // till row reaches to N
        while (row <= N) {
            while (column <= row - 1) {
               
                // Printing the pattern
                System.out.print("* ");
                column++;
            }
            row++;
            column = 0;
           
            // Print on new line after the next line
            System.out.println();
        }
   }
  
    public static void main(String[] args) {
       
        // Initialize a variable
        int N = 5;
       
        // Display the pattern
        printPyramidPattern(N);
    }
}

write your code here: Coding Playground

Output

Using Recursion

The following program prints the pyramid pattern using recursion:

Source Code

class HelloWorld {
   
      // function to print a row
    static void displayCurrentRow(int N)
    {
        // Base conditon
        if (N == 0)
            return;
        System.out.print("* ");
        // recursively calling displayCurrentRow()
        displayCurrentRow(N - 1);
    }
    // function to print the pattern
    static void printPyramidPattern(int N, int i)
    {
        // Base condition
        if (N == 0)
            return;
           
        displayCurrentRow(i);
        System.out.println();
        // Recursively call printPyramidPattern()
        printPyramidPattern(N - 1, i + 1);
    }
 
    public static void main(String[] args) {
       
        // Initialize a variable
        int N = 5;
       
        // Display the pattern
        printPyramidPattern(N, 1);
    }
}

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Output

Now let’s print the pyramid in the inverted form:

Source Code

class HelloWorld {
   
 
    // Function to print the pattern
    static void printPyramidPattern(int N)
    {
        
        //Print the pattern
        for (int index1 = 1; index1 <= N; index1++)
        {
          for (int index2 = 1; index2 < index1 ; index2++)
            {
                System.out.print(" ");
            }
          for (int index2 = index1; index2 <= N; index2++)
            {
                System.out.print("*" + " ");
            } 
            System.out.println();
        }
       
    }
 
    public static void main(String[] args) {
       
        // The number of rows that our pattern should have
        int N = 5;
       
        // Display the pattern
        printPyramidPattern(N);
    }
}

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Output

Conclusion

In this article, we discussed different types of pyramid patterns in Java. We believe that this article has provided you with a better understanding of loops in Java.