No longer maintained

This package is no longer maintained. See this statement for more info.

PHP-LCS

An implementation of the 'longest common subsequence' algorithm for PHP.

Installation and documentation

• Available as Composer package eloquent/lcs.
• API documentation available.

What is PHP-LCS?

PHP-LCS is a PHP implementation of an algorithm to solve the 'longest common subsequence' problem.

From Wikipedia - longest common subsequence problem:

The longest common subsequence (LCS) problem is to find the longest subsequence common to all sequences in a set of sequences (often just two). Note that subsequence is different from a substring, see substring vs. subsequence. It is a classic computer science problem, the basis of file comparison programs such as diff, and has applications in bioinformatics.

Usage

use Eloquent\Lcs\LcsSolver;

$solver = new LcsSolver;

$sequenceA = array('B', 'A', 'N', 'A', 'N', 'A');
$sequenceB = array('A', 'T', 'A', 'N', 'A');

// calculates the LCS to be array('A', 'A', 'N', 'A')
$lcs = $solver->longestCommonSubsequence($sequenceA, $sequenceB);

Elements in sequences can be anything. By default, sequence members are compared using the === operator. To customize this comparison, simply construct the solver with a custom comparator, like so:

use Eloquent\Lcs\LcsSolver;

$solver = new LcsSolver(
    function ($left, $right) {
        // return true if $left and $right are equal
    }
);