traversal

问题 Can anyone provide either code, pseudocode, or even provide good links to implementing DFS and BFS in plain JavaScript (No JQuery, or any helper libraries)? I've been trying to understand how to implement either traversal, but I can't seem to really distinguish the difference of a BFS and DFS implementation. If we want a concrete problem as an example: I want to traverse down the DOM at a given node, and get all the class names. (The only way I can think to traverse is to go through each

问题 I'm messing around with file lookups in python on a large hard disk. I've been looking at os.walk and glob. I usually use os.walk as I find it much neater and seems to be quicker (for usual size directories). Has anyone got any experience with them both and could say which is more efficient? As I say, glob seems to be slower, but you can use wildcards etc, were as with walk, you have to filter results. Here is an example of looking up core dumps. core = re.compile(r"core\.\d*") for root, dirs

问题 I have a Process table in SQL Server like this: workflowXML column has values like this: sample1 (ProcessID=1) workflowXML of sample1: <process> <Event type="start" id="StartEvent_1" name="Start"> <outgoing>SequenceFlow_0z7u86p</outgoing> <outgoing>SequenceFlow_1onkt3z</outgoing> </Event> <task type="" id="Task_0a7vu1x" name="D"> <incoming>SequenceFlow_108ajnm</incoming> <incoming>SequenceFlow_1onkt3z</incoming> <outgoing>SequenceFlow_01clcmz</outgoing> </task> <task type="goal" id="Task

问题 How can I get the tree form these pre/in order traversal: Pre: A,B,D,E,C,F,G,H in:E,D,B,A,G,F,H,C EDITED: MY Answer A / \ B C / \ D F / / \ E G H 回答1: EDIT: Correction, You don't have the correct answer, FGH is to the left of C. To verify just run the two algorithms against it: PreOrder(node) if node is null return Print(node) PreOrder(node.left) PreOrder(node.Right) InOrder(node) if node is null return InOrder(node.left) Print(node) InOrder(node.Right) You know that A is the root because it

问题 How can I construct a tree given its inorder and preorder traversal? I am just looking for an efficient algorithm. 回答1: A blatant copy and paste from Sun's (Oracle now, I guess...) forum: Question: Can anybody help me on how to construct Binary tree from inorder and postorder traversals,i just want to know the algorithm so that i can apply it. Answer: Let p_1 , p_2 ... p_n be the postorder traversal and let i_1 , i_2 ... i_n be the inorder traversal. From the postorder traversal we know that

问题 1How would I traverse an array from the centre outwards, visiting each cell only once? I can do it with a breadthfirst traversal by finding unvisited neighbours, but how could I do it with some kind of edit-distance traversal? I've been trying to figure it out on paper, but can't wrap my head around it. eg, in an array [ [5 6 8 9 0] [1 2 4 5 6] [5 4 0 2 1] [1 2 3 4 5] [1 2 3 4 5]] starting from the zero in the centre, we would visit the 4 at [1][2] then the 2 at [2][3] then the 3 at [3][2]

问题 Am trying to parse the below xml using TBXML. I want to create an array which contains all the item tag values. How can I traverse through the "item" tags? <root> <item> <northeast_area> <item> <new_england_north xsi:type="SOAP-ENC:Array" SOAP-ENC:arrayType="xsd:string[8]"> <item xsi:type="xsd:string">boston s, ma</item> <item xsi:type="xsd:string">providence, ri</item> <item xsi:type="xsd:string">boston, ma </item> <item xsi:type="xsd:string">portland, me</item> <item xsi:type="xsd:string"

问题 I'm supposed to traverse a Binary Seach Tree as preorder, inorder and postorder and insert the values into an Object[] in Java. I honestly have no clue how to do this and I need some advice. My function: public Object[] traversePreOrder() All I need are basically some ideas or hints on how to complete this task. If I traverse a tree as preorder Object[0] is obviously the value of the root. Then I continue in the left tree and insert the most left values in my array. Next I insert the right

问题 I am trying to implement a B+ tree myself, but I want to create a method that prints what elements does the B+ tree have. If I use a traversal(in or post order) I will get also the elements in the parent nodes, therefore I will have duplicate values. Is there a way to solve this thing? Thanks 回答1: Mark the nodes as you traverse them. Once the node is marked, it can't be traversed. 来源： https://stackoverflow.com/questions/9917715/b-tree-print-elements-is-order

问题 I am trying to iterate through a tree inorder in Lisp. So far, I managed building the Postorder traversal but inorder gives me headaches.. The tree's format is this: A / \ B C (A 2 B 0 C 2 D 0 E 0) / \ D E (defun traverseTreeMain (l) (traverseTree l nil) ) (defun traverseTree (l lc) (cond ((and (null l) (null lc)) nil) ((null l) (append nil (traverseTree lc nil))) ((=(cadr l) 0) (append (list (car l)) (traverseTree (cddr l) lc) )) ((= (cadr l) 1) (append nil (traverseTree (cddr l) (append (