Double the first element and move zero to end

Given an array\list containing integers, zero is considered an invalid number

and the rest of the other numbers are valid. If the two nearest valid numbers are equal

then double the value of the right one and make the left one 0.

ignore any comparison with zero

At last move all zeros to the right

Input:

2 4 5 0 0 5 5 4 8 6 0 6 8

Iteration Flow to understand the problem:

2 4 ....

2 4 5....

2 4 5 0 ...

2 4 5 0 0 .....

2 4 0 0 0 10 5...

2 4 0 0 0 10 5 4 8 0 0 12 8

Final Output Array:

2 4 10 5 4 8 12 8 0 0 0 0 0 

<?php

// Your code here!

$arr = [2,4,5,0,0,5,5,4,8,6,0,6,8];

$arr_count = count($arr);

$res = [];

for ($i = 0, $j=0; $i < $arr_count-1; $i++) {

    if($arr[$i]==0 && $i!=0){

        $arr[$i] = $arr[$i-1];

        $arr[$i-1] = 0;

    }

    else if($i!=0 && $arr[$i]!=0 && ($arr[$i] == $arr[$i-1])){

        $arr[$i-1] = 0;

    $arr[$i] = 2 * $arr[$i];

    $i++;

    }

    print_r($arr[$i]);

}