how to push associative array in php code example

Example 1: array_push php

<?php
$cesta = array("laranja", "morango");
array_push($cesta, "melancia", "batata");
print_r($cesta);
?>

Example 2: php array push

array_push ( array &$array [, mixed $... ] ) : int
or
$array[] = $var;

Example 3: php add to existing associative array

$a1=['aa'=>'123' , 'bb'=>'454'];

$a1 = array_merge( $a1 , ['a'=>1,'b'=>2] ) ;