Program to print hollow pyramid and diamond pattern

Prerequisite : Loops, If Else Statement

1. Hollow pyramid/triangle pattern
The pattern is similar to pyramid pattern. The only difference is, we will replace all internal ‘#’ characters by space character and we will 2*N-1 (N = number of rows in pattern) ‘#’ characters in last row.
Examples:

Input rows: 6
Output:
     #
    # #
   #   #
  #     #
 #       #
#         #
###########

C++

// CPP program to print a hollow pyramid pattern 
#include <iostream> 
using namespace std; 
void printPattern(int); 
int main() 
{ 
    int n = 6; 
  
    printPattern(n); 
} 
void printPattern(int n) 
{ 
    int i, j, k = 0; 
    for (i = 1; i <= n; i++) // row=6 
    { 
        // Print spaces 
        for (j = i; j < n; j++) { 
            cout << " "; 
        } 
        // Print # 
        while (k != (2 * i - 1)) { 
            if (k == 0 || k == 2 * i - 2) 
                cout << "#"; 
            else
                cout << " "; 
            k++; 
            ; 
        } 
        k = 0; 
        cout << endl; // print next row 
    } 
    // print last row 
    for (i = 0; i < 2 * n - 1; i++) { 
        cout << "#"; 
    } 
} 

Java

// JAVA program to print a hollow  
// pyramid pattern 
class GFG{ 
      
    public static void main(String args[]) 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j, k = 0; 
        for (i = 1; i <= n; i++) // row=6 
        { 
            // Print spaces 
            for (j = i; j < n; j++) { 
                System.out.print(" "); 
            } 
            // Print # 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    System.out.print("#"); 
                else
                    System.out.print(" "); 
                k++; 
                ; 
            } 
            k = 0; 
              
            // print next row 
            System.out.println();  
        } 
        // print last row 
        for (i = 0; i < 2 * n - 1; i++) { 
            System.out.print("#"); 
        } 
    } 
} 
  
/*This code is contributed by Nikita Tiwari.*/

Python

# Python program to print a hollow  
# pyramid pattern 
  
def printPattern( n) : 
    k = 0
    for i in range(1,n+1) : #row 6 
      
        # Print spaces 
        for j in range(i,n) : 
            print(' ', end='') 
          
        # Print # 
        while (k != (2 * i - 1)) : 
            if (k == 0 or k == 2 * i - 2) : 
                print('#', end='') 
            else : 
                print(' ', end ='') 
            k = k + 1
        k = 0; 
        print ("") # print next row 
          
    # print last row 
    for i in range(0, 2 * n -1) : 
        print ('#', end = '') 
  
# Driver code  
n = 6
printPattern(n) 
  
# This code is contributed by Nikita Tiwari. 

c#

// C# program to print a hollow  
// pyramid pattern 
using System; 
class GFG{ 
      
    public static void Main() 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j, k = 0; 
        for (i = 1; i <= n; i++) // row=6 
        { 
            // Print spaces 
            for (j = i; j < n; j++) { 
                Console.Write(" "); 
            } 
            // Print # 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    Console.Write("#"); 
                else 
                    Console.Write(" "); 
                k++; 
                ; 
            } 
            k = 0; 
              
            // print next row 
            Console.WriteLine();  
        } 
        // print last row 
        for (i = 0; i < 2 * n - 1; i++) { 
            Console.Write("#"); 
        } 
    } 
} 
  
/*This code is contributed by vt_m.*/ 

PHP

<?php 
// php program to print a 
// hollow pyramid pattern 
  
function printPattern($n) 
{ 
    $k = 0; 
      
    // row=6 
    for ($i = 1; $i <= $n; $i++)  
    { 
          
        // Print spaces 
        for ($j = $i; $j < $n; $j++)  
        { 
            echo " "; 
        } 
          
        // Print # 
        while ($k != (2 * $i - 1))  
        { 
            if ($k == 0 || $k == 2 *  
                             $i - 2) 
                echo "#"; 
            else
                echo " "; 
            $k++; 
        } 
        $k = 0; 
          
        // print next row 
        echo "\n";  
    } 
      
    // print last row 
    for ($i = 0; $i < 2 * $n - 1; $i++) 
    { 
        echo "#"; 
    } 
} 
  
//Driver Code 
$n = 6; 
printPattern($n); 
  
// This code is contributed by mits  
?> 

Output:

     #
    # #
   #   #
  #     #
 #       #
#         #
###########

2. Hollow inverted pyramid/triangle pattern
Examples:

Input rows: 6

Output:
###########
 #       #
  #     #
   #   #
    # #
     #

C++

// CPP program to print a hollow 
// inverted pyramid pattern 
  
#include <iostream> 
using namespace std; 
void printPattern(int); 
int main() 
{ 
    int n = 6; 
  
    printPattern(n); 
} 
void printPattern(int n) 
{ 
    int i, j; 
    for (i = 1; i <= n; i++) { 
        // Print  spaces 
        for (j = 1; j < i; j++) { 
            cout << " "; 
        } 
  
        // Print hollow inverted pyramid 
        for (j = 1; j <= (n * 2 - (2 * i - 1)); j++) { 
  
            if (i == 1 || j == 1 || j == (n * 2 - (2 * i - 1))) { 
                cout << "#"; 
            } else { 
                cout << " "; 
            } 
        } 
  
        // next line 
        cout << endl; 
    } 
} 

Java

// Java program to print a hollow 
// inverted pyramid pattern 
class GFG{ 
  
    public static void main(String args[]) 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j; 
        for (i = 1; i <= n; i++) { 
      
            // Print spaces 
            for (j = 1; j < i; j++) { 
                System.out.print(" "); 
            } 
      
            // Print hollow inverted pyramid 
            for (j = 1; j <= (n * 2 - (2 * i - 1)); 
                                        j++) { 
      
                if (i == 1 || j == 1 ||  
                    j == (n * 2 - (2 * i - 1))) { 
                    System.out.print("#"); 
                } 
                else { 
                    System.out.print(" "); 
                } 
            } 
      
            // next line 
            System.out.println(); 
        } 
    } 
} 
  
/*This code is contributed by Nikita Tiwari.*/

Python

# Python program to print a hollow 
# inverted pyramid pattern 
  
def printPattern(n) : 
      
    for i in range(1,n+1) : 
          
        # Print spaces 
        for j in range(1,i) : 
            print (" ",end="") 
              
        # Print hollow inverted pyramid 
        for j in range(1,(n * 2 - (2 * i - 1))  
                                       +1) : 
            if (i == 1 or j == 1 or 
               j == (n * 2 - (2 * i - 1))) : 
                print ("#", end="")  
            else : 
                print(" ", end="")  
                  
        # next line 
        print (""), 
  
# Driver code 
n = 6
printPattern(n) 
  
# This code is contributed by Nikita Tiwari. 

c#

// C# program to print a hollow 
// inverted pyramid pattern 
using System; 
class GFG{ 
  
    public static void Main() 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j; 
        for (i = 1; i <= n; i++) { 
      
            // Print spaces 
            for (j = 1; j < i; j++) { 
             Console.Write(" "); 
            } 
      
            // Print hollow inverted pyramid 
            for (j = 1; j <= (n * 2 - (2 * i - 1)); 
                                        j++) { 
      
                if (i == 1 || j == 1 ||  
                    j == (n * 2 - (2 * i - 1))) { 
                    Console.Write("#"); 
                } 
                else { 
                    Console.Write(" "); 
                } 
            } 
      
            // next line 
            Console.WriteLine(); 
        } 
    } 
} 
  
/*This code is contributed by vt_m.*/ 

PHP

<?php 
// php program to print a hollow 
// inverted pyramid pattern 
  
function printPattern($n) 
{ 
    for ($i = 1; $i <= $n; $i++)  
    { 
          
        // Print spaces 
        for ($j = 1; $j < $i; $j++)  
        { 
            echo " "; 
        } 
  
        // Print hollow inverted pyramid 
        for ($j = 1; $j <= ($n *  
             2 - (2 * $i - 1)); $j++) 
        { 
  
            if ($i == 1 || $j == 1 ||  
                $j == ($n * 2 - (2 * $i - 1))) 
            { 
                echo "#"; 
            }  
            else 
            { 
                echo " "; 
            } 
        } 
  
        // next line 
        echo "\n"; 
    } 
} 
  
    // Driver Code 
    $n = 6; 
    printPattern($n); 
  
// This code is contributed by mits  
?> 

Output:

###########
 #       #
  #     #
   #   #
    # #
     #

3.Hollow diamond pattern
Examples:

Input rows: 6
Output:
     #
    # #
   #   #
  #     #
 #       #
#         #
 #         #
  #       #
   #     #
    #   #
     # #
      #

C++

// CPP program to print a hollow 
// diamond pattern 
#include <iostream> 
using namespace std; 
void printPattern(int); 
int main() 
{ 
    int n = 6; 
  
    printPattern(n); 
} 
void printPattern(int n) 
{ 
    int i, j, space, k = 0; 
  
    // Print upper triangle 
    for (i = 1; i <= n; i++) { 
        // Print spaces 
        for (j = 1; j <= n - i; j++) { 
            cout << " "; 
        } 
        // Print # 
        while (k != (2 * i - 1)) { 
            if (k == 0 or k == 2 * i - 2) 
                cout << "#"; 
            else
                cout << " "; 
            k++; 
        } 
        k = 0; 
        // move to next row 
        cout << endl; 
    } 
    n--; 
    // Print lower triangle 
    for (i = n; i >= 1; i--) { 
        // Print spaces 
        for (j = 0; j <= n - i; j++) { 
            cout << " "; 
        } 
        // Print # 
        k = 0; 
        while (k != (2 * i - 1)) { 
            if (k == 0 or k == 2 * i - 2) 
                cout << "#"; 
            else
                cout << " "; 
            k++; 
        } 
        cout << endl; 
    } 
} 

Java

// JAVA program to print a hollow 
// diamond pattern 
class GFG{ 
      
    public static void main(String args[]) 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j, space, k = 0; 
      
        // Print upper triangle 
        for (i = 1; i <= n; i++) { 
      
            // Print spaces 
            for (j = 1; j <= n - i; j++) { 
                System.out.print(" "); 
            } 
      
            // Print # 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    System.out.print("#"); 
                else
                    System.out.print(" "); 
                k++; 
            } 
            k = 0; 
      
            // move to next row 
            System.out.println(); 
        } 
        n--; 
      
        // Print lower triangle 
        for (i = n; i >= 1; i--) { 
      
            // Print spaces 
            for (j = 0; j <= n - i; j++) { 
                System.out.print(" "); 
            } 
      
            // Print # 
            k = 0; 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    System.out.print("#"); 
                else
                    System.out.print(" "); 
                k++; 
            } 
            System.out.println(); 
        } 
    } 
} 
  
/*This code is contributed by Nikita Tiwari.*/

Python

# Python program to print a hollow 
# diamond pattern 
  
def printPattern(n) : 
    k = 0; 
  
    # Print upper triangle 
    for i in range(1,n+1) : 
  
        # Print spaces 
        for j in range(1,n-i+1) : 
            print(" ",end="") 
              
        # Print # 
        while (k != (2 * i - 1)) : 
            if (k == 0 or k == 2 * i - 2) : 
                print("#",end="") 
            else : 
                print(" ",end="") 
            k = k + 1
              
        k = 0
  
        # move to next row 
        print(""), 
      
    n = n - 1
  
    # Print lower triangle 
    for i in range (n,0,-1) : 
        # Print spaces 
        for j in range(0,n-i+1) : 
            print(" ",end="") 
              
        # Print # 
        k = 0
        while (k != (2 * i - 1)) : 
            if (k == 0 or k == 2 * i - 2) : 
                print("#",end="") 
            else : 
                print(" ",end="") 
            k = k + 1
          
        print(""), 
              
# Driver code 
n = 6
printPattern(n) 
  
# This code is contributed by Nikita Tiwari. 

c#

// C# program to print a hollow 
// diamond pattern 
using System; 
class GFG{ 
      
    public static void Main() 
    { 
        int n = 6; 
      
        printPattern(n); 
    } 
      
    static void printPattern(int n) 
    { 
        int i, j, k = 0; 
      
        // Print upper triangle 
        for (i = 1; i <= n; i++) { 
      
            // Print spaces 
            for (j = 1; j <= n - i; j++) { 
                Console.Write(" "); 
            } 
      
            // Print # 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    Console.Write("#"); 
                else 
                Console.Write(" "); 
                k++; 
            } 
            k = 0; 
      
            // move to next row 
               Console.WriteLine(); 
        } 
        n--; 
      
        // Print lower triangle 
        for (i = n; i >= 1; i--) { 
      
            // Print spaces 
            for (j = 0; j <= n - i; j++) { 
                Console.Write(" "); 
            } 
      
            // Print # 
            k = 0; 
            while (k != (2 * i - 1)) { 
                if (k == 0 || k == 2 * i - 2) 
                    Console.Write("#"); 
                else 
                    Console.Write(" "); 
                k++; 
            } 
            Console.WriteLine(); 
        } 
    } 
} 
  
/*This code is contributed by vt_m.*/ 

PHP

<?php 
// php program to print a  
// hollow diamond pattern 
  
function printPattern($n) 
{ 
      
    $k = 0; 
  
    // Print upper triangle 
    for ($i = 1; $i <= $n; $i++)  
    { 
          
        // Print spaces 
        for ($j = 1; $j <= $n - $i; $j++)  
        { 
            echo " "; 
        } 
          
        // Print # 
        while ($k != (2 * $i - 1))  
        { 
            if ($k == 0 or $k == 2 * $i - 2) 
                echo "#"; 
            else
                echo " "; 
            $k++; 
        } 
        $k = 0; 
          
        // move to next row 
        echo "\n"; 
    } 
    $n--; 
      
    // Print lower triangle 
    for ($i = $n; $i >= 1; $i--) 
    { 
          
        // Print spaces 
        for ($j = 0; $j <= $n - $i; $j++)  
        { 
            echo " "; 
        } 
          
        // Print # 
        $k = 0; 
        while ($k != (2 * $i - 1))  
        { 
            if ($k == 0 or $k == 2 * $i - 2) 
                echo "#"; 
            else
                echo " "; 
            $k++; 
        } 
        echo "\n"; 
    } 
} 
  
    // Driver Code 
    $n = 6; 
    printPattern($n); 
  
// This Code is contributed by mits  
?> 

Output:

     
     #
    # #
   #   #
  #     #
 #       #
#         #
 #         #
  #       #
   #     #
    #   #
     # #
      #

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