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<?php $a= array ( 1 => 0, 2 => 1, 3 => 2, 4 => 3, 5 => 1, 6 => 0 ); class node { var $children; public function __construct(){ $this->children = array(); } } $tree = array(); foreach ($a as $q => $p){ if(!isset($tree[$p])) $tree[$p] = new node; if(!isset($tree[$q])) $tree[$q] = new node; $mark[$p]=FALSE; $mark[$q]=FALSE; array_push($tree[$p]->children,$q); } function dfs(&$ans,$node){ global $tree, $mark; $mark[$node] = TRUE; $ans = array(); foreach($tree[$node]->children as $child) if(!$mark[$child]){ $ans[$child]=$child; dfs($ans[$child],$child); } } $parent=1; dfs($ans,$parent); print_r($ans[1]); ?>
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
Warning: Undefined array key 1 in /in/auMW3 on line 47
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined offset: 1 in /in/auMW3 on line 47
Output for 7.3.32 - 7.3.33
Output for 5.1.3 - 5.1.6, 5.2.0 - 5.2.17
Notice: Undefined offset: 1 in /in/auMW3 on line 47
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.2
Strict Standards: var: Deprecated. Please use the public/private/protected modifiers in /in/auMW3 on line 15 Notice: Undefined offset: 1 in /in/auMW3 on line 47
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/auMW3 on line 16
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
Parse error: parse error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/auMW3 on line 16
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_OLD_FUNCTION' or `T_FUNCTION' or `T_VAR' or `'}'' in /in/auMW3 on line 16
Process exited with code 255.
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