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<?php $sentence = 'Jumpy Qbert grawlix'; $usage = count_chars(strtolower($sentence), 3); $alphabet = range('a', 'z'); var_export([ 'Sentence' => $sentence, 'Total Length' => strlen($sentence), 'Alphabetical Length' => preg_match_all('~[a-z]~', $sentence, $letters), 'Unused Letters' => array_diff($alphabet, $letters), 'Duplicated Letters' => array_diff(array_count_values($letters), [1]), ]);
based on WPslB
Output for 8.0.0alpha1 - alpha2
Warning: Array to string conversion in /in/IUTV1 on line 10 Warning: array_count_values(): Can only count string and integer values, entry skipped in /in/IUTV1 on line 11 array ( 'Sentence' => 'Jumpy Qbert grawlix', 'Total Length' => 19, 'Alphabetical Length' => 15, 'Unused Letters' => array ( 0 => 'a', 1 => 'b', 2 => 'c', 3 => 'd', 4 => 'e', 5 => 'f', 6 => 'g', 7 => 'h', 8 => 'i', 9 => 'j', 10 => 'k', 11 => 'l', 12 => 'm', 13 => 'n', 14 => 'o', 15 => 'p', 16 => 'q', 17 => 'r', 18 => 's', 19 => 't', 20 => 'u', 21 => 'v', 22 => 'w', 23 => 'x', 24 => 'y', 25 => 'z', ), 'Duplicated Letters' => array ( ), )
Output for 7.2.0 - 7.2.31, 7.3.0 - 7.3.19, 7.4.0 - 7.4.7
Notice: Array to string conversion in /in/IUTV1 on line 10 Warning: array_count_values(): Can only count STRING and INTEGER values! in /in/IUTV1 on line 11 array ( 'Sentence' => 'Jumpy Qbert grawlix', 'Total Length' => 19, 'Alphabetical Length' => 15, 'Unused Letters' => array ( 0 => 'a', 1 => 'b', 2 => 'c', 3 => 'd', 4 => 'e', 5 => 'f', 6 => 'g', 7 => 'h', 8 => 'i', 9 => 'j', 10 => 'k', 11 => 'l', 12 => 'm', 13 => 'n', 14 => 'o', 15 => 'p', 16 => 'q', 17 => 'r', 18 => 's', 19 => 't', 20 => 'u', 21 => 'v', 22 => 'w', 23 => 'x', 24 => 'y', 25 => 'z', ), 'Duplicated Letters' => array ( ), )