Print lower triangular matrix pattern from given array

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Given an array, print the array in 2D form where upper triangle has values 0 and lower triangle has values increasing prefix sizes (First row has prefix of size 1, second row has prefix of size 2, ..)
Examples :

Input :  1 2 3 4 5
Output : 1 0 0 0 0
         1 2 0 0 0
         1 2 3 0 0
         1 2 3 4 0
         1 2 3 4 5 

Input :  1 2 3
Output : 1 0 0 
         1 2 0 
         1 2 3

C++

// C++ implementation to print 
// given array in 2D form 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to print pattern 
void printPattern(int arr[], int n) 
{ 
    // array to store the final output 
    int b[n][n]; 
    for (int i = 0; i < n; i++) 
    { 
       for (int j = 0; j < n; j++) 
         
       // if i > j then insert arr[j]  
       // in 2D array b[i][j] 
       if (i >= j) 
          b[i][j] = arr[j]; 
  
       else
         
          // insert zero in array b[i][j] 
          b[i][j] = 0; 
    } 
  
    // printing pattern in 2-D array i.e, 
    // printing 2D array b[i][j] 
    for (int i = 0; i < n; i++) 
    { 
      for (int j = 0; j < n; j++) 
         cout << b[i][j] << " "; 
      cout << endl; 
    } 
} 
  
// Driver code 
int main() 
{ 
    int arr[] = { 1, 2, 3, 4, 5 }; 
    int n = sizeof(arr) / sizeof(arr[0]); 
    printPattern(arr, n); 
    return 0; 
} 

Java

// Java implementation to print 
// given array in 2D form 
import java.io.*; 
  
class GFG  
{ 
    // Function to print pattern 
    static void printPattern(int arr[], int n) 
    { 
        // array to store the final output 
        int b[][] = new int[n][n]; 
        for (int i = 0; i < n; i++) 
        { 
            for (int j = 0; j < n; j++) 
                  
                // if i > j then insert arr[j]  
                // in 2D array b[i][j] 
                if (i >= j) 
                    b[i][j] = arr[j]; 
              
                else
                      
                    // insert zero in array b[i][j] 
                    b[i][j] = 0; 
        } 
      
        // printing pattern in 2-D array i.e, 
        // printing 2D array b[i][j] 
        for (int i = 0; i < n; i++) 
        { 
            for (int j = 0; j < n; j++) 
                System.out.print(b[i][j] +" "); 
            System.out.println(); 
        } 
    } 
  
    // Driver code 
    public static void main (String[] args)  
    { 
        int arr[] = { 1, 2, 3, 4, 5 }; 
        int n = arr.length; 
        printPattern(arr, n); 
          
    } 
} 
// This code is contributed by vt_m. 

Python3

# Python3 implementation to print 
# given array in 2D form 
  
# Function to print pattern 
def printPattern(arr, n): 
  
    # array to store the final output 
    b = [[0 for i in range(n)]  
            for i in range(n)] 
  
    for i in range(0, n): 
      
        for j in range(0, n): 
          
        # if i > j then insert arr[j]  
        # in 2D array b[i][j] 
            if (i >= j): 
                b[i][j] = arr[j]; 
  
            else: 
          
                # insert zero in array b[i][j] 
                b[i][j] = 0; 
      
    # printing pattern in 2-D array i.e, 
    # printing 2D array b[i][j] 
    for i in range(0, n): 
      
        for j in range(0, n): 
            print(b[i][j], end = " "); 
        print(); 
      
# Driver code 
arr = [ 1, 2, 3, 4, 5 ]; 
n = len(arr); 
printPattern(arr, n); 
      
# This code is contributed by 
# Shivi_Aggarwal 

C#

// C# implementation to print 
// given array in 2D form 
using System; 
  
namespace Array 
{ 
public class GFG 
{      
    // Function to print pattern          
    static void printPattern(int []arr, int n) 
    { 
        // array to store the final output 
        int[,] b = new int[n,n]; 
          
        for (int i = 0; i < n; i++) 
        { 
            for (int j = 0; j < n; j++) 
                  
                // if i > j then insert arr[j]  
                // in 2D array b[i][j] 
                if (i >= j) 
                    b[i,j] = arr[j]; 
              
                else
                      
                    // insert zero in array b[i][j] 
                    b[i,j] = 0; 
        } 
      
        // printing pattern in 2-D array i.e, 
        // printing 2D array b[i][j] 
        for (int i = 0; i < n; i++) 
        { 
            for (int j = 0; j < n; j++) 
                Console.Write(b[i,j] + " "); 
            Console.WriteLine(); 
        } 
    } 
  
    // Driver code 
    public static void Main() 
    { 
        int []arr = { 1, 2, 3, 4, 5 }; 
        int n = arr.Length; 
        printPattern(arr, n); 
          
    } 
  
}  
} 
  
// This code is contributed by Sam007 

PHP

<?php 
// PHP implementation to print  
// lower triangular matrix pattern 
  
// Function to print pattern 
function printPattern(array $arr, $n) 
{ 
    // $array to store the  
    // final output 
    $b; 
    for ($i = 0; $i < $n; $i++) 
    { 
    for ($j = 0; $j < $n; $j++) 
          
    // if $i > $j then insert $arr[$j]  
    // in 2D $array $b[$i][$j] 
    if ($i >= $j) 
        $b[$i][$j] = $arr[$j]; 
  
    else
          
        // insert zero in  
        // $array $b[$i][$j] 
        $b[$i][$j] = 0; 
    } 
  
    // printing pattern in 2-D  
    // $array i.e, printing 2D  
    // $array $b[$i][$j] 
    for ($i = 0; $i < $n; $i++) 
    { 
    for ($j = 0; $j < $n; $j++) 
        echo $b[$i][$j]." "; 
    echo "\n"; 
    } 
} 
  
// Driver code 
$arr = array(1, 2, 3, 4, 5); 
$n = sizeof($arr) / sizeof($arr[0]); 
printPattern($arr, $n); 
  
// This code is contributed by Mithun Kumar 
?> 

Javascript

<script> 
  
// JavaScript implementation to print 
// given array in 2D form 
  
// Function to print pattern 
function printPattern(arr, n) 
{ 
    // array to store the final output 
    var b = Array.from(Array(n), ()=>Array(n)); 
    for (var i = 0; i < n; i++) 
    { 
       for (var j = 0; j < n; j++) 
         
       // if i > j then insert arr[j]  
       // in 2D array b[i][j] 
       if (i >= j) 
          b[i][j] = arr[j]; 
  
       else
         
          // insert zero in array b[i][j] 
          b[i][j] = 0; 
    } 
  
    // printing pattern in 2-D array i.e, 
    // printing 2D array b[i][j] 
    for (var i = 0; i < n; i++) 
    { 
      for (var j = 0; j < n; j++) 
         document.write( b[i][j] + " "); 
      document.write("<br>"); 
    } 
} 
  
// Driver code 
var arr = [1, 2, 3, 4, 5]; 
var n = arr.length; 
printPattern(arr, n); 
  
  
</script>

Output:

Time complexity: O(n^2) for given n, where n is size of given array

Auxiliary space: O(n^2)

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