Sequential search, or linear search, is the simplest searching algorithm. Indeed, given it’s brute force approach of just traversing a collection from the first to last element, it’s hard to justify calling it an algorithm at all. However, here’s an example in PHP:

function sequential_search($needle,$haystack) {
for($i = 0; $i < count($haystack); $i++) { if ($needle == $i) return true; } return false; }

Here's an example of how you would use this algorithm to look for the number 3 inside an array:


$haystack = array(1,2,3,4);
$needle = 3;
$success = sequential_search($needle, $haystack);