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<?php header('Content-Type: application/json; charset="utf-8"'); /** * Helper function * * @param array $d flat data, implementing a id/parent id (adjacency list) structure * @param mixed $r root id, node to return * @param string $pk parent id index * @param string $k id index * @param string $c children index * @return array */ function makeRecursive($d, $r = 0, $pk = 'parent', $k = 'id', $c = 'children') { $m = array(); foreach ($d as $e) { isset($m[$e[$pk]]) ?: $m[$e[$pk]] = array(); isset($m[$e[$k]]) ?: $m[$e[$k]] = array(); $m[$e[$pk]][] = array_merge($e, array($c => &$m[$e[$k]])); } return $m[$r][0]; // remove [0] if there could be more than one root nodes } echo json_encode(makeRecursive(array( array('id' => 5273, 'parent' => 0, 'name' => 'John Doe'), array('id' => 6032, 'parent' => 5273, 'name' => 'Sally Smith'), array('id' => 6034, 'parent' => 6032, 'name' => 'Mike Jones'), array('id' => 6035, 'parent' => 6034, 'name' => 'Jason Williams'), array('id' => 6036, 'parent' => 5273, 'name' => 'Sara Johnson'), array('id' => 6037, 'parent' => 5273, 'name' => 'Dave Wilson'), array('id' => 6038, 'parent' => 6037, 'name' => 'Amy Martin'), )));
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
{"id":5273,"parent":0,"name":"John Doe","children":[{"id":6032,"parent":5273,"name":"Sally Smith","children":[{"id":6034,"parent":6032,"name":"Mike Jones","children":[{"id":6035,"parent":6034,"name":"Jason Williams","children":[]}]}]},{"id":6036,"parent":5273,"name":"Sara Johnson","children":[]},{"id":6037,"parent":5273,"name":"Dave Wilson","children":[{"id":6038,"parent":6037,"name":"Amy Martin","children":[]}]}]}
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 {"id":5273,"parent":0,"name":"John Doe","children":[{"id":6032,"parent":5273,"name":"Sally Smith","children":[{"id":6034,"parent":6032,"name":"Mike Jones","children":[{"id":6035,"parent":6034,"name":"Jason Williams","children":[]}]}]},{"id":6036,"parent":5273,"name":"Sara Johnson","children":[]},{"id":6037,"parent":5273,"name":"Dave Wilson","children":[{"id":6038,"parent":6037,"name":"Amy Martin","children":[]}]}]}

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