In this practice-oriented lesson, we'll be tackling Advanced Array Manipulation, a crucial topic in any technical interview. PHP arrays are versatile and powerful data structures used in almost every aspect of programming. Mastering advanced manipulation techniques can streamline your code, optimize time complexity, and solve complex problems efficiently.

Let's assume we have the following problem — given two arrays sorted in ascending order, we need to merge them into a single sorted array.

The expected algorithm for this task uses two pointers, one for each array, and compares the elements pointed to by these pointers, appending the smaller one to the result array. If one of the arrays is exhausted, it simply appends the remaining elements from the other array. This is a classic example of the Two Pointer Technique, frequently employed in array manipulation problems.

Here's how you can implement the solution in PHP:

php
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1<?php
2
3function mergeSortedArrays($array1, $array2) {
4    $mergedArray = [];
5    $i = 0;
6    $j = 0;
7
8    while ($i < count($array1) && $j < count($array2)) {
9        if ($array1[$i] <= $array2[$j]) {
10            $mergedArray[] = $array1[$i];
11            $i++;
12        } else {
13            $mergedArray[] = $array2[$j];
14            $j++;
15        }
16    }
17
18    // Append remaining elements of array1, if any
19    while ($i < count($array1)) {
20        $mergedArray[] = $array1[$i];
21        $i++;
22    }
23
24    // Append remaining elements of array2, if any
25    while ($j < count($array2)) {
26        $mergedArray[] = $array2[$j];
27        $j++;
28    }
29
30    return $mergedArray;
31}
32
33// Example usage
34$array1 = [1, 3, 5];
35$array2 = [2, 4, 6];
36
37$mergedArray = mergeSortedArrays($array1, $array2);
38echo "Merged Array: ";
39print_r($mergedArray);
40// Output: 1 2 3 4 5 6
41
42?>

Grasping this lesson's subject matter is key to becoming proficient in PHP and acing your technical interviews. After gaining a comprehensive understanding of the basics, take time to dive into the exercises. Remember, the goal isn't just to memorize these algorithms but to learn how to dissect and tackle real-world problems using these tools. Let's proceed to practice mastering PHP array manipulation techniques!