Traversal interview questions

Implement a function that returns whether two binary trees have identical structure and node values.

Implement a function that returns the maximum depth from root to leaf in a binary tree.

Implement a function that mirrors a binary tree by swapping the left and right children of every node.

Implement a function that returns the kth smallest value in a binary search tree.

Implement a function that finds the lowest common ancestor of two nodes in a binary search tree.

Build a binary tree data structure with the essential insert, traverse, and search operations.

Implement a function that returns the values of a binary tree grouped by level from top to bottom.

Implement a function that determines whether one binary tree appears as a subtree of another.

Implement breadth-first traversal of a directed graph, visiting nodes level by level from a start vertex.

Implement a function that locates the node in a mirrored DOM tree occupying the same path as a given node.

Implement a function that counts the number of distinct islands of connected cells in a 2D binary grid.

Implement a function that walks an arbitrarily nested structure and applies a transform to every leaf value.

Implement depth-first traversal of a directed graph, exploring each branch fully before backtracking.

Implement a function that checks whether a target word can be traced through adjacent cells in a 2D character grid.

Implement a function that returns all DOM elements containing every one of the specified class names.

Implement a function that returns all DOM elements whose computed style matches a given property and value.

Implement a function that walks a DOM tree and returns every descendant element matching a given tag name.

Implement a function that produces a deep copy of a connected, undirected graph given a reference node.

Implement a simplified HTML sanitizer that strips out unsafe tags and attributes from a given DOM tree.

Implement a function that serializes a tree-shaped object into a pretty-printed HTML string with indentation.

Implement a function that determines whether a given undirected graph forms a valid tree.

Implement a function that walks a 2D matrix in clockwise spiral order and returns the visited values.

Implement a function that returns every grid cell from which water can flow to both the Pacific and Atlantic oceans.

Implement a function that flattens a nested object into a single-level object using dot-delimited keys.

Implement a function that determines whether a binary tree satisfies the binary search tree ordering invariant.

Implement functions that convert a binary tree to a string and reconstruct the same tree back from that string.

Implement Dijkstra's algorithm to compute shortest paths from a source vertex in a weighted graph.

Implement a function that finds all DOM elements matching an ancestor-to-descendant tag-name hierarchy.

Implement a function that finds the deepest common ancestor whose hiding would conceal every target element.

Implement a function that walks an HTML document's headings and builds a nested table of contents.

Implement a function that gathers the text content lying between two DOM nodes in document order.

Implement a function that returns a topological ordering of nodes in a directed acyclic graph.