Master recursive thinking through binary trees — from traversals to path problems
Interactive BST — insert nodes and animate inorder, preorder, postorder traversals
TreeNode class, recursion on trees, traversals, and the BST property.
Return a list of every node's value using preorder traversal.
Check whether a target value exists anywhere in the tree.
Find the height of a binary tree using recursive DFS.
Count the total number of nodes in a binary tree.
Return all node values in inorder (sorted for BSTs) using recursion.
Check if any root-to-leaf path sums to a target value.