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<?php function getSimilarSubstring($a, $b) { if(!strlen($a) || !strlen($b)) { return ''; } if(false!==strpos($a, $b)) { return $b; } $length = strlen($b); for($i=$length-1; $i>0; $i--) { for($j=0; $j<$length-$i; $j++) { if($result = getSimilarSubstring($a, substr($b, $j, $i))) { return $result; } } } return ''; } $word_a = "superman"; $word_b = "stermastein"; //$word_a = 'afk'; //$word_b = 'fk'; var_dump(getSimilarSubstring($word_a, $word_b));
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(1) "s"

preferences:
206.01 ms | 405 KiB | 309 Q