Print the given pattern recursively

Given a positive integer n. Print the inverted triangular pattern (as described in the examples below) using the recursive approach.

Examples:

Input : n = 5
Output : 
* * * * *
* * * *
* * *
* *
*

Input : n = 7
Output :
* * * * * * *
* * * * * *
* * * * * 
* * * *
* * *
* *
*

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Method 1 (Using two recursive functions): One recursive function is used to get the row number and the other recursive function is used to print the stars of that particular row.

Algorithm:

printPatternRowRecur(n)
    if n < 1
        return
        
    print "* "
    printPatternRowRecur(n-1)

printPatternRecur(n)
    if n < 1
        return
    
    printPatternRowRecur(n)
    print "\n"
    printPatternRecur(n-1)

C++

// C++ implementation to print the given 
// pattern recursively 
#include <bits/stdc++.h> 
using namespace std; 
  
// function to print the 'n-th' row of the 
// pattern recursively 
void printPatternRowRecur(int n) 
{ 
    // base condition 
    if (n < 1) 
        return; 
          
    // print the remnaining stars of the n-th row 
    // recursively     
    cout << "* "; 
    printPatternRowRecur(n-1); 
} 
  
void printPatternRecur(int n) 
{ 
    // base condition 
    if (n < 1) 
        return; 
      
    // print the stars of the n-th row     
    printPatternRowRecur(n);     
      
    // move to next line 
    cout << endl; 
      
    // print stars of the remaining rows recursively 
    printPatternRecur(n-1); 
      
} 
  
// Driver program to test above 
int main() 
{ 
    int n = 5; 
    printPatternRecur(n); 
    return 0; 
} 

Java

// java implementation to print the given 
// pattern recursively 
import java.io.*; 
  
class GFG 
{ 
    // function to print the 'n-th' row  
    // of the pattern recursively 
    static void printPatternRowRecur(int n) 
    { 
        // base condition 
        if (n < 1) 
            return; 
              
        // print the remnaining stars  
        // of the n-th row recursively  
        System.out.print( "* "); 
        printPatternRowRecur(n - 1); 
    } 
      
    static void printPatternRecur(int n) 
    { 
        // base condition 
        if (n < 1) 
            return; 
          
        // print the stars of the n-th row  
        printPatternRowRecur(n);  
          
        // move to next line 
        System.out.println (); 
          
        // print stars of the  
        // remaining rows recursively 
        printPatternRecur(n - 1); 
          
    } 
  
    // Driver program to test above 
    public static void main (String[] args)  
    { 
        int n = 5; 
        printPatternRecur(n); 
          
    } 
} 
//This code is contributed by vt_m 

Python3

# Python 3 implementation  
# to print the given  
# pattern recursively 
  
# function to print the 
# 'n-th' row of the 
# pattern recursively 
def printPatternRowRecur(n): 
  
    # base condition 
    if (n < 1): 
        return
          
    # print the remnaining  
    # stars of the n-th row 
    # recursively  
    print("*", end = " ") 
    printPatternRowRecur(n - 1) 
  
def printPatternRecur(n): 
  
    # base condition 
    if (n < 1): 
        return
      
    # print the stars of 
    # the n-th row  
    printPatternRowRecur(n)  
      
    # move to next line 
    print("") 
      
    # print stars of the  
    # remaining rows recursively 
    printPatternRecur(n - 1) 
      
# Driver Code 
n = 5
printPatternRecur(n) 
  
# This code is contributed 
# by Smitha 

C#

// C# implementation to print the given 
// pattern recursively 
using System; 
class GFG 
{ 
    // function to print the 'n-th' row  
    // of the pattern recursively 
    static void printPatternRowRecur(int n) 
    { 
        // base condition 
        if (n < 1) 
            return; 
              
        // print the remnaining stars  
        // of the n-th row recursively  
        Console.Write( "* "); 
        printPatternRowRecur(n - 1); 
    } 
      
    static void printPatternRecur(int n) 
    { 
        // base condition 
        if (n < 1) 
            return; 
          
        // print the stars of the n-th row  
        printPatternRowRecur(n);  
          
        // move to next line 
         Console.WriteLine(); 
          
        // print stars of the  
        // remaining rows recursively 
        printPatternRecur(n - 1); 
          
    } 
  
    // Driver program to test above 
    public static void Main()  
    { 
        int n = 5; 
        printPatternRecur(n); 
          
    } 
} 
//This code is contributed by vt_m 

PHP

<?php 
// php implementation to print the given 
// pattern recursively 
  
// function to print the 'n-th' row  
// of the pattern recursively 
function printPatternRowRecur($n) 
{ 
      
    // base condition 
    if ($n < 1) 
        return; 
          
    // print the remnaining stars of  
    // the n-th row recursively  
    echo "* "; 
    printPatternRowRecur($n-1); 
} 
  
function printPatternRecur($n) 
{ 
    // base condition 
    if ($n < 1) 
        return; 
      
    // print the stars of the n-th row  
    printPatternRowRecur($n);  
      
    // move to next line 
    echo "\n"; 
      
    // print stars of the remaining 
    // rows recursively 
    printPatternRecur($n-1); 
      
} 
  
    // Driver code  
    $n = 5; 
    printPatternRecur($n); 
  
// This code is contributed by mits  
?> 

Output:

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

Method 2 (Using single recursive function): This approach uses a single recursive function to print the entire pattern.

Algorithm:

printPatternRecur(n, i)
    if n < 1
        return
    
    if i <= n
        print "* "
        printPatternRecur(n, i+1)
        
    else
        print "\n"
        printPatternRecur(n-1, 1)

C++

// C++ implementation to print the given pattern recursively 
#include <bits/stdc++.h> 
  
using namespace std; 
  
// function to print the given pattern recursively 
void printPatternRecur(int n, int i) 
{ 
    // base condition 
    if (n < 1) 
        return; 
      
    // to print the stars of a particular row 
    if (i <= n) 
    { 
        cout << "* "; 
          
        // recursively print rest of the stars  
        // of the row 
        printPatternRecur(n, i + 1); 
    }     
      
    else
    { 
        // change line 
        cout << endl; 
          
        // print stars of the remaining rows recursively 
        printPatternRecur(n-1, 1); 
    } 
} 
  
// Driver program to test above 
int main() 
{ 
    int n = 5; 
    printPatternRecur(n, 1); 
    return 0;     
} 

Java

// java implementation to  
// print the given pattern recursively 
import java.io.*; 
  
class GFG { 
      
    // function to print the 
    // given pattern recursively 
    static void printPatternRecur(int n, int i) 
    { 
        // base condition 
        if (n < 1) 
            return; 
          
        // to print the stars of  
        // a particular row 
        if (i <= n) 
        { 
            System.out.print ( "* "); 
              
            // recursively print rest   
            // of the stars of the row 
            printPatternRecur(n, i + 1); 
        }  
          
        else
        { 
            // change line 
            System.out.println( ); 
              
            // print stars of the  
            // remaining rows recursively 
            printPatternRecur(n - 1, 1); 
        } 
    } 
      
    // Driver program  
    public static void main (String[] args)  
    { 
        int n = 5; 
        printPatternRecur(n, 1); 
          
    } 
} 
  
// This code is contributed by vt_m 

Python 3

# Python3 implementation to print the  
# given pattern recursively 
  
# function to print the given pattern 
# recursively 
def printPatternRecur(n, i): 
  
    # base condition 
    if (n < 1): 
        return
      
    # to print the stars of a 
    # particular row 
    if (i <= n): 
      
        print("* ", end = "") 
          
        # recursively print rest of 
        # the stars of the row 
        printPatternRecur(n, i + 1) 
      
    else: 
      
        # change line 
        print("") 
          
        # print stars of the remaining 
        # rows recursively 
        printPatternRecur(n-1, 1) 
  
# Driver program to test above 
n = 5
printPatternRecur(n, 1) 
  
# This code is contributed by Smitha 

C#

// C# implementation to  
// print the given pattern recursively 
using System; 
class GFG { 
      
    // function to print the 
    // given pattern recursively 
    static void printPatternRecur(int n, int i) 
    { 
        // base condition 
        if (n < 1) 
            return; 
          
        // to print the stars of  
        // a particular row 
        if (i <= n) 
        { 
            Console.Write ( "* "); 
              
            // recursively print rest  
            // of the stars of the row 
            printPatternRecur(n, i + 1); 
        }  
          
        else
        { 
            // change line 
            Console.WriteLine( ); 
              
            // print stars of the  
            // remaining rows recursively 
            printPatternRecur(n - 1, 1); 
        } 
    } 
      
    // Driver program  
    public static void Main ()  
    { 
        int n = 5; 
        printPatternRecur(n, 1); 
          
    } 
} 
  
// This code is contributed by vt_m 

PHP

<?php 
// php implementation to print 
// the given pattern recursively 
  
// function to print the given  
// pattern recursively 
function printPatternRecur($n, $i) 
{ 
      
    // base condition 
    if ($n < 1) 
        return; 
      
    // to print the stars of  
    // a particular row 
    if ($i <= $n) 
    { 
        echo "* "; 
          
        // recursively print rest of  
        // the stars  of the row 
        printPatternRecur($n, $i + 1); 
    }  
      
    else
    { 
        // change line 
        echo "\n"; 
          
        // print stars of the remaining 
        // rows recursively 
        printPatternRecur($n - 1, 1); 
    } 
} 
  
    // Driver code 
    $n = 5; 
    printPatternRecur($n, 1); 
  
// This code is contributed by mits  
?> 

Output:

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

This article is contributed by Ayush Jauhari. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@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.

My Personal Notes

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

Java

Python3

C#

PHP

C++

Java

Python 3

C#

PHP

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