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Print window pattern

The "Print Window Pattern" is a programming problem that involves printing a specific pattern of asterisks (*) and spaces to resemble a window. The pattern is constructed based on the height provided as input. The code provided is a C program that solves this problem and generates the desired pattern.

Problem Statement

The goal is to create a pattern that resembles a window, where the outer frame consists of asterisks and the inner space is left empty. The pattern should have a specific height, which determines the number of rows and columns.

For example, if the height is 5, the pattern would look like this:

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

If the height is 9, the pattern would look like this:

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

The goal is to generate this pattern dynamically based on the input height, making it adaptable to different sizes.

Algorithm and Pseudocode

The algorithm to solve this problem is as follows:

  1. Define a function called printPattern that takes the height as a parameter.
  2. Print the value of height to indicate the current pattern's height.
  3. Calculate the midpoint by dividing the height by 2.
  4. Iterate through each row and column using nested for loops.
  5. At each position, check if the current row or column is at the boundary of the pattern or at the midpoint.
  6. If any of the above conditions are met, print an asterisk (*), indicating the outer frame of the window.
  7. Otherwise, print a space, indicating the inner space of the window.
  8. Print a newline character after each row is completed.
  9. Repeat until all rows and columns have been processed.
  10. End the function.
  11. In the main function, call the printPattern function with different height values to test and generate the desired patterns.

The pseudocode representation of the algorithm:


function printPattern(height):
    print "Height: ", height
    mid = height / 2
    for i from 0 to height:
        for j from 0 to height:
            if (i == 0 or i + 1 == height or j == 0 or j + 1 == height or i == mid or j == mid or (height % 2 == 0 and (i + 1 == mid or j + 1 == mid))):
                print "* "
            else:
                print "  "
        print newline
    end function

function main:
    printPattern(5)
    printPattern(9)
    printPattern(7)
    printPattern(8)
end function

Code Solution

//  C program for
//  Print window pattern
#include <stdio.h>

void printPattern(int height)
{
	printf("\n Height : %d  \n\n", height);
	// When height is Even
	int mid = height / 2;
	for (int i = 0; i < height; ++i)
	{
		for (int j = 0; j < height; ++j)
		{
			if (i == 0 || i + 1 == height || 
                j == 0 || j + 1 == height || 
                (i == mid) || (j == mid) || 
                (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
			{
				// Include star
				printf("* ");
			}
			else
			{
				printf("  ");
			}
		}
		printf("\n");
	}
}
int main(int argc, char
	const *argv[])
{
	// Test
	printPattern(5);
	printPattern(9);
	printPattern(7);
	printPattern(8);
	return 0;
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
/*
    Java Program
    Print window pattern
*/
public class Pattern
{
	public void printPattern(int height)
	{
		System.out.println("\n Height : " + height + " \n");
		// When height is Even
		int mid = height / 2;
		for (int i = 0; i < height; ++i)
		{
			for (int j = 0; j < height; ++j)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					System.out.print("* ");
				}
				else
				{
					System.out.print("  ");
				}
			}
			System.out.print("\n");
		}
	}
	public static void main(String[] args)
	{
		Pattern task = new Pattern();
		// Test
		task.printPattern(5);
		task.printPattern(9);
		task.printPattern(7);
		task.printPattern(8);
	}
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
// Include header file
#include <iostream>
using namespace std;
/*
    C++ Program
    Print window pattern
*/
class Pattern
{
	public: void printPattern(int height)
	{
		cout << "\n Height : " << height << " \n" << endl;
		// When height is Even
		int mid = height / 2;
		for (int i = 0; i < height; ++i)
		{
			for (int j = 0; j < height; ++j)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					cout << "* ";
				}
				else
				{
					cout << "  ";
				}
			}
			cout << "\n";
		}
	}
};
int main()
{
	Pattern *task = new Pattern();
	// Test
	task->printPattern(5);
	task->printPattern(9);
	task->printPattern(7);
	task->printPattern(8);
	return 0;
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
// Include namespace system
using System;
/*
    Csharp Program
    Print window pattern
*/
public class Pattern
{
	public void printPattern(int height)
	{
		Console.WriteLine("\n Height : " + height + " \n");
		// When height is Even
		int mid = height / 2;
		for (int i = 0; i < height; ++i)
		{
			for (int j = 0; j < height; ++j)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					Console.Write("* ");
				}
				else
				{
					Console.Write("  ");
				}
			}
			Console.Write("\n");
		}
	}
	public static void Main(String[] args)
	{
		Pattern task = new Pattern();
		// Test
		task.printPattern(5);
		task.printPattern(9);
		task.printPattern(7);
		task.printPattern(8);
	}
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
package main
import "fmt"
/*
    Go Program
    Print window pattern
*/
type Pattern struct {}
func getPattern() * Pattern {
	var me *Pattern = &Pattern {}
	return me
}
func(this Pattern) printPattern(height int) {
	fmt.Println("\n Height : ", height, " \n")
	// When height is Even
	var mid int = height / 2
	for i := 0 ; i < height ; i++ {
		for j := 0 ; j < height ; j++ {
			if i == 0 || i + 1 == height || 
			j == 0 || j + 1 == height || 
			(i == mid) || (j == mid) || 
			(height % 2 == 0 && (i + 1 == mid || j + 1 == mid)) {
				// Include star
				fmt.Print("* ")
			} else {
				fmt.Print("  ")
			}
		}
		fmt.Print("\n")
	}
}
func main() {
	var task * Pattern = getPattern()
	// Test
	task.printPattern(5)
	task.printPattern(9)
	task.printPattern(7)
	task.printPattern(8)
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
<?php
/*
    Php Program
    Print window pattern
*/
class Pattern
{
	public	function printPattern($height)
	{
		echo("\n Height : ".$height." \n\n");
		// When height is Even
		$mid = (int)($height / 2);
		for ($i = 0; $i < $height; ++$i)
		{
			for ($j = 0; $j < $height; ++$j)
			{
				if ($i == 0 || $i + 1 == $height || 
                    $j == 0 || $j + 1 == $height || 
                    ($i == $mid) || ($j == $mid) || 
                    ($height % 2 == 0 && ($i + 1 == $mid || $j + 1 == $mid)))
				{
					// Include star
					echo("* ");
				}
				else
				{
					echo("  ");
				}
			}
			echo("\n");
		}
	}
}

function main()
{
	$task = new Pattern();
	// Test
	$task->printPattern(5);
	$task->printPattern(9);
	$task->printPattern(7);
	$task->printPattern(8);
}
main();

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
/*
    Node JS Program
    Print window pattern
*/
class Pattern
{
	printPattern(height)
	{
		console.log("\n Height : " + height + " \n");
		// When height is Even
		var mid = parseInt(height / 2);
		for (var i = 0; i < height; ++i)
		{
			for (var j = 0; j < height; ++j)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					process.stdout.write("* ");
				}
				else
				{
					process.stdout.write("  ");
				}
			}
			process.stdout.write("\n");
		}
	}
}

function main()
{
	var task = new Pattern();
	// Test
	task.printPattern(5);
	task.printPattern(9);
	task.printPattern(7);
	task.printPattern(8);
}
main();

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
#    Python 3 Program
#    Print window pattern
class Pattern :
	def printPattern(self, height) :
		print("\n Height : ", height ," \n")
		#  When height is Even
		mid = int(height / 2)
		i = 0
		while (i < height) :
			j = 0
			while (j < height) :
				if (i == 0 or i + 1 == height or 
                    j == 0 or j + 1 == height or
                    (i == mid) or(j == mid) or
                (height % 2 == 0 and(i + 1 == mid or j + 1 == mid))) :
					#  Include star
					print("* ", end = "")
				else :
					print("  ", end = "")
				
				j += 1
			
			print(end = "\n")
			i += 1
		
	

def main() :
	task = Pattern()
	#  Test
	task.printPattern(5)
	task.printPattern(9)
	task.printPattern(7)
	task.printPattern(8)

if __name__ == "__main__": main()

Output

 Height :  5

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

 Height :  9

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

 Height :  7

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

 Height :  8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
#    Ruby Program
#    Print window pattern
class Pattern 
	def printPattern(height) 
		print("\n Height : ", height ," \n", "\n")
		#  When height is Even
		mid = height / 2
		i = 0
		while (i < height) 
			j = 0
			while (j < height) 
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid))) 
					#  Include star
					print("* ")
				else
 
					print("  ")
				end

				j += 1
			end

			print("\n")
			i += 1
		end

	end

end

def main() 
	task = Pattern.new()
	#  Test
	task.printPattern(5)
	task.printPattern(9)
	task.printPattern(7)
	task.printPattern(8)
end

main()

Output

 Height : 5 

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

 Height : 9 

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

 Height : 7 

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

 Height : 8 

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

/*
    Scala Program
    Print window pattern
*/
class Pattern()
{
	def printPattern(height: Int): Unit = {
		println("\n Height : " + height + " \n");
		// When height is Even
		var mid: Int = height / 2;
		var i: Int = 0;
		while (i < height)
		{
			var j: Int = 0;
			while (j < height)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					print("* ");
				}
				else
				{
					print("  ");
				}
				j += 1;
			}
			print("\n");
			i += 1;
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: Pattern = new Pattern();
		// Test
		task.printPattern(5);
		task.printPattern(9);
		task.printPattern(7);
		task.printPattern(8);
	}
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
/*
    Swift 4 Program
    Print window pattern
*/
class Pattern
{
	func printPattern(_ height: Int)
	{
		print("\n Height : ", height ," \n");
		// When height is Even
		let mid: Int = height / 2;
		var i: Int = 0;
		while (i < height)
		{
			var j: Int = 0;
			while (j < height)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					print("* ", terminator: "");
				}
				else
				{
					print("  ", terminator: "");
				}
				j += 1;
			}
			print(terminator: "\n");
			i += 1;
		}
	}
}
func main()
{
	let task: Pattern = Pattern();
	// Test
	task.printPattern(5);
	task.printPattern(9);
	task.printPattern(7);
	task.printPattern(8);
}
main();

Output

 Height :  5

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

 Height :  9

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

 Height :  7

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

 Height :  8

* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
* * * * * * * *
*     * *     *
*     * *     *
* * * * * * * *
/*
    Kotlin Program
    Print window pattern
*/
class Pattern
{
	fun printPattern(height: Int): Unit
	{
		println("\n Height : " + height + " \n");
		// When height is Even
		val mid: Int = height / 2;
		var i: Int = 0;
		while (i < height)
		{
			var j: Int = 0;
			while (j < height)
			{
				if (i == 0 || i + 1 == height || 
                    j == 0 || j + 1 == height || 
                    (i == mid) || (j == mid) || 
                    (height % 2 == 0 && (i + 1 == mid || j + 1 == mid)))
				{
					// Include star
					print("* ");
				}
				else
				{
					print("  ");
				}
				j += 1;
			}
			print("\n");
			i += 1;
		}
	}
}
fun main(args: Array < String > ): Unit
{
	val task: Pattern = Pattern();
	// Test
	task.printPattern(5);
	task.printPattern(9);
	task.printPattern(7);
	task.printPattern(8);
}

Output

 Height : 5

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

 Height : 9

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

 Height : 7

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

 Height : 8

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

Output Explanation

The code provided generates the following output:

Height: 5

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

Height: 9

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

Height: 7

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

Height: 8

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

Time Complexity

The time complexity of the given code is O(n^2), where n is the height of the pattern. This is because there are nested loops iterating from 0 to the height value, resulting in a quadratic relationship between the input size and the number of operations performed.

Last updated on by Kalkicode




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