<?php
$str = "23456789ABCDEGHJKMNPQRSTUVXYZabcdeghjkmnpqrstuvxyz";
$excludes = ['cp','cb','ck','c6','c9','rn','rm','mm','co','do','cl','db','qp','qb','dp','ww'];
for ($i = 0; $i < 1000000; $i++)
if (preg_match('/cp|cb|ck|c6|c9|rn|rm|mm|co|do|cl|db|qp|qb|dp|ww/', $str)) break;
for ($i = 0; $i < 1000000; $i++)
foreach($excludes as $ex)
if (false !== strpos($str, $ex)) break 2;
echo "regexp: " . ($t1 - $t0) . "\n";
echo "strpos: " . ($t2 - $t1) . "\n";
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