PHP str_pad to print string patterns

str_pad:
Pad a string to a certain length with another string.

Syntax:- str_pad (input, pad_length, pad_string_value, pad_type)
It returns the padded string.

Parameters Description

input:-The input string.
pad_length:-If the value of pad_length is negative, less than, or equal to the length of the input string, no padding takes place, and input is returned.
pad_string_input:-The pad_string may be truncated if the required number of padding characters can’t be evenly divided by the pad_string’s length.
pad_type:-Optional argument pad_type can be STR_PAD_RIGHT, STR_PAD_LEFT, or STR_PAD_BOTH. If pad_type is not specified it is assumed to be STR_PAD_RIGHT.

Print simple patterns like below using single line of code under loop.
Examples:

Input : 5
Output :
    *
   **
  ***
 ****
*****

Input : 6
Output :
     *
    **
   ***
  ****
 *****
******

<?php
// PHP program to print a pattern using only
// one loop.

function generatePattern($n)
{
    // Initialize the string
    $str = "";

    // Iterate for n lines
    for ($i=0 ; $i<$n ; $i++)
    {
        // Concatenate the string
        $str .= "*";
        echo str_pad($str, $n, " ", STR_PAD_LEFT), "\n";
    }
}

// Driver code
$n = 6;
generatePattern($n);
?>

Output:

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