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<?php function find_parent($ar, $id='id', $pid='pid') { foreach($ar as $v) $t[$v[$id]] = $v; foreach ($t as $k => $item){ if( $item[$pid] ){ if( ! isset($t[$item[$pid]]['parent'][$item[$pid]]) ) $t[$item[$id]]['parent'][$item[$pid]] =& $t[$item[$pid]]; } } return $t; } function find_child($ar, $id='id', $pid='pid') { foreach($ar as $v) $t[$v[$id]] = $v; foreach ($t as $k => $item){ if( $item[$pid] ) { $t[$item[$pid]]['child'][$item[$id]] =& $t[$k]; } } return $t; } $data = array( array('ID'=>1, 'PARENT'=>0, 'NAME'=>'祖父'), array('ID'=>2, 'PARENT'=>1, 'NAME'=>'父亲'), array('ID'=>3, 'PARENT'=>1, 'NAME'=>'叔伯'), array('ID'=>4, 'PARENT'=>2, 'NAME'=>'自己'), array('ID'=>5, 'PARENT'=>4, 'NAME'=>'儿子'), ); $p = find_parent($data, 'ID', 'PARENT'); $c = find_child($data, 'ID', 'PARENT'); Print_r ($c);

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