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<?php $str = "pwwkew"; function lengthOfLongestSubstring($s) { $len = strlen($s); $letter = []; $result = 0; for ($i = 0; $i < $len; $i++) { while (in_array($s[$i], $letter)) { array_shift($letter); } $letter[] = $s[$i]; if (count($letter) > $result) { $result = count($letter); } } return $result; } echo lengthOfLongestSubstring($str);
Output for 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.21, 8.5.0 - 8.5.6
3

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51.61 ms | 730 KiB | 3 Q