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<?php $input = ["a", "b"]; function search($input) { $result = $input; foreach($input as $a) foreach($input as $b) $result []= $a . $b; return array_walk(array_unique($result)); } echo json_encode(search($input));
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Notice: Only variables should be passed by reference in /in/u7Q0k on line 12 Fatal error: Uncaught ArgumentCountError: array_walk() expects at least 2 arguments, 1 given in /in/u7Q0k:12 Stack trace: #0 /in/u7Q0k(12): array_walk(Array) #1 /in/u7Q0k(15): search(Array) #2 {main} thrown in /in/u7Q0k on line 12
Process exited with code 255.
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Only variables should be passed by reference in /in/u7Q0k on line 12 Warning: array_walk() expects at least 2 parameters, 1 given in /in/u7Q0k on line 12 null
Output for 7.3.32 - 7.3.33
Warning: array_walk() expects at least 2 parameters, 1 given in /in/u7Q0k on line 12 null
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28
Strict Standards: Only variables should be passed by reference in /in/u7Q0k on line 12 Warning: array_walk() expects at least 2 parameters, 1 given in /in/u7Q0k on line 12 null
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/u7Q0k on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/u7Q0k on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/u7Q0k on line 3
Process exited with code 255.

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