Ly Quoc Phong lyquocphong

## minsubstring.php
<?php

$str = 'abbaacdbcab';
$chars = ['a', 'b', 'c'];

echo "Expected: bca | Result: ".findMinWinSubString($str, $chars)."\n";

$str = 'xyyzyzyx';
$chars = ['x', 'y', 'z'];
	<?php

	$str = 'abbaacdbcab';
	$chars = ['a', 'b', 'c'];

	echo "Expected: bca \| Result: ".findMinWinSubString($str, $chars)."\n";

	$str = 'xyyzyzyx';
	$chars = ['x', 'y', 'z'];