Arrays and Iteration

Find Maximum

Scan the array once, keeping the largest value seen so far. The replay highlights when a candidate replaces the running maximum.

Algorithm

Basic Implementation

basic.php 
<?php
$arr = [3, 1, 4, 1, 5, 9, 2, 6];
$best = $arr[0];
for ($i = 1; $i < count($arr); $i++) {
	if ($arr[$i] > $best) {
		$best = $arr[$i];
	}
}
echo $best . "\n";

Complexity

  • Time: O(n)
  • Space: O(1)

Implementation notes

  • Keep the explicit control flow. Library shortcuts would hide the state changes this lesson is meant to replay.
  • The final output is intentionally small and deterministic for cross-language comparison.
execution replay The checked-in replay follows the language-neutral state table for `array-find-max`.
cross-language comparison This PHP DSA version keeps the same data and final output as every other DSA book in this wave.