postorder

I want to define a generalized tail recursive tree traversal that works for all kinds of multi-way trees. This works fine with pre-order and level-order, but I'm having trouble to implement post order traversals. Here is the multi-way tree I am working with: Desired order: EKFBCGHIJDA As long as I don't care about tail recursion post order traversal is easy: const postOrder = ([x, xs]) => { xs.forEach(postOrder); console.log(`${x}`); }; const Node = (x, ...xs) => ([x, xs]); const tree = Node("a", Node("b", Node("e"), Node("f", Node("k"))), Node("c"), Node("d", Node("g"), Node("h"), Node("i"),

Consider a binary tree with the following properties: An internal node (non-leaf node) has a value 1 if it has two children. A leaf node has a value 0 since it has no children. A level order traversal on the tree would generate a string of 1s and 0s (by printing the weird value at each node as they are visited). Now given this string construct the binary tree and perform a post order traversal on the tree. The post order string should be the output of the program. For example: Input String is 111001000 . Create a binary tree from this. Then perform the post order traversal on the tree which

I understand pre-order, in-order, and post-order tree traversal algorithms just fine. ( Reference ). I understand a few uses: in-order for traversing binary search trees in order, pre-order for cloning a tree. But I can't for the life of me come up with a real world task that I'd need post-order traversal to accomplish. Can you give me an example? And: can you give me any better uses for pre-order traversal? Edit: Can anyone give me an example other than expression trees and RPN? Is that really all post-order is good for? Topological sorting is a post-order traversal of trees (or directed

I'm trying to construct a full binary tree (full meaning that every non leaf node has two leaf nodes connecting to it, i.e. node->right and node->left are != NULL ) given only the postorder traversal of the tree. In addition, I am given whether or not the node in the postorder traversal is a leaf node or not. The given postorder traversal looks like this: 2(1.000000e+00) 3(1.000000e+00) (1.000000e+00 1.000000e+00) 1(1.000000e+00) (1.000000e+00 2.000000e+00) for example, where a line of the format "%d(%le)" is a leaf node and "(%le %le)" is a non-leaf node. Normally you can't construct a tree

I have a recursive function that returns all subtree nodes, given the starting root node. private IEnumerable<Node> getAllNodesRecursively(Node subnode) { foreach (Node node in subnode.Nodes) getAllNodesRecursively(node); yield return subnode; } For the following tree structure: A | +--B | +--C | | | +--D | +--E When I try to iterate as such: foreach (Node n in getAllNodesRecursively(a)) { Console.WriteLine(n); } the function returns the only the A value. I wish to use yield-return with recursion and retrieve elements in the Preorder (A, B, C, D, E in this example). (If I put the yield return