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<?php $lettersArray = ['A','C','E','G']; $letters = array_combine($lettersArray, array_fill(0,count($lettersArray), [])); var_dump($letters);
Output for 5.6.38, 7.0.33, 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array(4) { ["A"]=> array(0) { } ["C"]=> array(0) { } ["E"]=> array(0) { } ["G"]=> array(0) { } }
preferences:
208.58 ms | 408 KiB | 5 Q