Commit 4fe5c16

committed

Adding bottom view binary tree problem solution

- Solution based on https://www.geeksforgeeks.org/bottom-view-binary-tree/ - Modified `.gitignore` to ignore Visual Studio's files

1 parent 43ed1bc commit 4fe5c16Copy full SHA for 4fe5c16

File tree

+50

-1

lines changed

+50

-1

lines changed

Lines changed: 2 additions & 1 deletion

Lines changed: 5 additions & 0 deletions

Some generated files are not rendered by default. Learn more about customizing how changed files appear on GitHub.

Lines changed: 3 additions & 0 deletions

Lines changed: 40 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,40 @@`
	`1`	`+const HashMap = require('hashmap');`
	`2`	`+const Queue = require('../../../Queue');`
	`3`	`+`
	`4`	`+// Determines the bottom view of a binary tree`
	`5`	`+// Takes a BinaryTree as a parameter`
	`6`	`+// Returns an integer array`
	`7`	`+// Time complexity: O(n) where n is the number of nodes in the tree`
	`8`	`+`
	`9`	`+module.exports = function bottomView(binaryTree) {`
	`10`	`+ if (binaryTree == null \|\| binaryTree.root == null) {`
	`11`	`+ return [];`
	`12`	`+ }`
	`13`	`+`
	`14`	`+ // root's horizontal distance = 0`
	`15`	`+ const horizontalDistance = 0;`
	`16`	`+`
	`17`	`+ // create a map to track most recent visited nodes per hd`
	`18`	`+ const hdToNodeValue = new HashMap();`
	`19`	`+`
	`20`	`+ // perform bfs`
	`21`	`+ const q = new Queue();`
	`22`	`+ q.enqueue([binaryTree.root, horizontalDistance]);`
	`23`	`+`
	`24`	`+ while (q.length() > 0) {`
	`25`	`+ const currentNodeTuple = q.dequeue();`
	`26`	`+ const currentNode = currentNodeTuple[0];`
	`27`	`+ const currentHd = currentNodeTuple[1];`
	`28`	`+ hdToNodeValue.set(currentHd, currentNode.value);`
	`29`	`+`
	`30`	`+ if (currentNode.leftChild != null && currentNode.leftChild.value != null) {`
	`31`	`+ q.enqueue([currentNode.leftChild, currentHd - 1]);`
	`32`	`+ }`
	`33`	`+`
	`34`	`+ if (currentNode.rightChild != null && currentNode.rightChild.value != null) {`
	`35`	`+ q.enqueue([currentNode.rightChild, currentHd + 1]);`
	`36`	`+ }`
	`37`	`+ }`
	`38`	`+`
	`39`	`+ return hdToNodeValue.values();`
	`40`	`+};`

Comments

(0)