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.

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

C++

Java

Python3

C#

PHP

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Java

Python 3

C#

PHP

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