php how to make the multidimensional array to si code example

Example 1: convert multidimensional array to single array php

$singleArray = []; 
foreach ($parentArray as $childArray) 
{ 
    foreach ($childArray as $value) 
    { 
    $singleArray[] = $value; 
    } 
}

Example 2: multidimensional array in php

<?php 
/* 
There are 3 Types of array in php  
1. Indexed arrays - Arrays with a numeric index
2. Associative arrays - Arrays with named keys
3. Multidimensional arrays - Arrays containing one or more arrays

This is the third one - Multidimensional arrays
*/

$carsModel = array
  (
  array("Maruti",21,28),
  array("BMW",05,75),
  array("Tata",25,12),
  array("Land Rover",11,20)
  );
?>