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<?php $one_array_key = ['A', 'A', 'A', 'B', 'B', 'B']; $second_array_values = ['arn1', 'arn2', 'arn3', 'arn4', 'arn5', 'arn6']; $result = []; foreach ($one_array_key as $index => $value) { $result[$value][] = $second_array_values[$index]; } var_export($result);

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