Program to print solid and hollow square patterns

For any given number n, print Hollow and solid Squares and Rhombus made with stars(*).
Examples:

Input : n = 4
Output : 

Solid Square:
****
****
****
****

Hollow Square:
****
*  *
*  *
****

1. Solid Square : Solid Square is easiest among all given patterns. To print Solid square with n rows, we should use two loops iterating n times both. Where the outer loop is used for numbers of rows and the inner loop is used for printing all stars in a particular row.
2. Hollow Square : Hollow Square requires a little bit improvisation. Here we should again use two loops, where 1st and last row must have all n-stars and remaining rows have stars only in 1st and last column. 

C++

// C++ program to print
// hollow and solid square patterns

#include <bits/stdc++.h>
using namespace std;

// Function for hollow square
void hollowSquare(int rows)
{
    int i, j;
    for (i=1; i<=rows; i++)
    {
        // Print stars for each solid rows
        if (i==1 || i==rows)
            for (j=1; j<=rows; j++)
                cout << "*";

        // stars for hollow rows
        else
            for (j=1; j<=rows; j++)
                if (j==1 || j==rows)
                    cout << "*";
                else
                    cout << " ";

        // Move to the next line/row
        cout << "\n";
    }
}

// Function for Solid square
void solidSquare(int rows)
{
    int i, j;
    for (i=1; i<=rows; i++)
    {
        // Print stars after spaces
        for (j=1; j<=rows; j++)
            cout << "*";

        // Move to the next line/row
        cout << "\n";
    }

}

// Utility program to print all patterns
void printPattern(int rows)
{
    cout << "\nSolid Square:\n";
    solidSquare(rows);

    cout << "\nHollow Square:\n";
    hollowSquare(rows);
}

// Driver program
int main()
{
    int rows = 5;
    printPattern (rows);
    return 0;
}

Java

// Java program to print
// hollow and solid square patterns

class GFG
{
    // Function for hollow square
    static void hollowSquare(int rows)
    {
        int i, j;
        for (i = 1; i <= rows; i++)
        {
            // Print stars for each solid rows
            if (i == 1 || i == rows)
                for (j = 1; j <= rows; j++)
                    System.out.print("*");

            // stars for hollow rows
            else
                for (j = 1; j <= rows; j++)
                    if (j == 1 || j == rows)
                        System.out.print("*");
                    else
                        System.out.print(" ");

            // Move to the next line/row
            System.out.print("\n");
        }
    }

    // Function for Solid square
    static void solidSquare(int rows)
    {
        int i, j;
        for (i = 1; i <= rows; i++)
        {
            // Print stars after spaces
            for (j = 1; j <= rows; j++)
                System.out.print("*");

            // Move to the next line/row
            System.out.print("\n");
        }

    }

    // Utility program to print all patterns
    static void printPattern(int rows)
    {
        System.out.print("\nSolid Square:\n");
        solidSquare(rows);

        System.out.print("\nHollow Square:\n");
        hollowSquare(rows);
    }

    // Driver program
    public static void main (String[] args)
    {
        int rows = 5;
        printPattern (rows);
    }
}

// This code is contributed by Anant Agarwal.

Python3

# Python3 program to print
# hollow and solid square patterns

# Function for hollow square
def hollowSquare(rows):

    for i in range(1, rows + 1):

        # Print stars for each solid rows
        if (i == 1 or i == rows):
            for j in range(1, rows + 1):
                print("*", end = "")

        # stars for hollow rows
        else:
            for j in range(1, rows + 1):
                if (j == 1 or j == rows):
                    print("*", end = "")
                else:
                    print(end = " ")

        # Move to the next line/row
        print()

# Function for Solid square
def solidSquare(rows):

    for i in range(1, rows):

        # Print stars after spaces
        for j in range(1, rows + 1):
            print("*", end = "")

        # Move to the next line/row
        print()

# Utility program to print all patterns
def printPattern(rows):

    print("Solid Square:")
    solidSquare(rows)

    print("\nHollow Square:")
    hollowSquare(rows)

# Driver Code
rows = 5
printPattern (rows)

# This code is contributed by
# Mohit kumar 29

C#

// C# program to print
// hollow and solid square patterns
using System;

class GFG
{
    // Function for hollow square
    static void hollowSquare(int rows)
    {
        int i, j;
        for (i = 1; i <= rows; i++)
        {
            // Print stars for each solid rows
            if (i == 1 || i == rows)
                for (j = 1; j <= rows; j++)
                    Console.Write("*");

            // stars for hollow rows
            else
                for (j = 1; j <= rows; j++)
                    if (j == 1 || j == rows)
                        Console.Write("*");
                    else
                        Console.Write(" ");

            // Move to the next line/row
            Console.WriteLine();
        }
    }

    // Function for Solid square
    static void solidSquare(int rows)
    {
        int i, j;
        for (i = 1; i <= rows; i++)
        {
            // Print stars after spaces
            for (j = 1; j <= rows; j++)
                Console.Write("*");

            // Move to the next line/row
            Console.WriteLine();
        }

    }

    // Utility program to print all patterns
    static void printPattern(int rows)
    {
        Console.Write("\nSolid Square:\n");
        solidSquare(rows);

        Console.Write("\nHollow Square:\n");
        hollowSquare(rows);
    }

    // Driver program
    public static void Main ()
    {
        int rows = 5;
        printPattern (rows);
    }
}

// This code is contributed by vt_m.

PHP

<?php
// php program to print hollow
// and solid square patterns

// Function for hollow square
function hollowSquare($rows)
{
    for ($i = 1; $i <= $rows; $i++)
    {

        // Print stars for each solid rows
        if ($i == 1 || $i == $rows)
            for ($j = 1; $j <= $rows; $j++)
                echo "*";

        // stars for hollow rows
        else
            for ($j = 1; $j <= $rows; $j++)
                if ($j == 1 || $j == $rows)
                    echo "*";
                else
                    echo " ";

        // Move to the next line/row
        echo "\n";
    }
}

// Function for Solid square
function solidSquare($rows)
{
    for ($i = 1; $i <= $rows; $i++)
    {
        // Print stars after spaces
        for ($j = 1; $j <= $rows; $j++)
            echo "*";

        // Move to the next line/row
        echo "\n";
    }

}

// Utility program to
// print all patterns
function printPattern($rows)
{
    echo "\nSolid Square:\n";
    solidSquare($rows);

    echo "\nHollow Square:\n";
    hollowSquare($rows);
}

    // Driver code
    $rows = 5;
    printPattern ($rows);

// This code is contributed by mits
?>

Javascript

<script>

      // JavaScript program to print
      // hollow and solid square patterns

      // Function for hollow square
      function hollowSquare(rows) {
        var i, j;
        for (i = 1; i <= rows; i++) {
          // Print stars for each solid rows
          if (i == 1 || i == rows)
            for (j = 1; j <= rows; j++) document.write("*");

          // stars for hollow rows
          else
            for (j = 1; j <= rows; j++)
              if (j == 1 || j == rows) document.write("*");
              else document.write("  ");

          // Move to the next line/row
          document.write("<br>");
        }
      }

      // Function for Solid square
      function solidSquare(rows) {
        var i, j;
        for (i = 1; i <= rows; i++) {
          // Print stars after spaces
          for (j = 1; j <= rows; j++) document.write("*");

          // Move to the next line/row
          document.write("<br>");
        }
      }

      // Utility program to print all patterns
      function printPattern(rows) {
        document.write("Solid Square:<br>");
        solidSquare(rows);

        document.write("<br>Hollow Square:<br>");

        hollowSquare(rows);
      }

      // Driver program
      var rows = 5;
      printPattern(rows);

</script>

Output : 

Solid Square:
*****
*****
*****
*****
*****

Hollow Square:
*****
*   *
*   *
*   *
*****

Time Complexity: O(n²), where n represents the given input.
Auxiliary Space: O(1), no extra space is required, so it is a constant.

If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.