Sr Power Electronics Engineer, Kuiper Government Solutions (KGS)

Amazon

Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has both p and q as descendants (where we allow a node to be a descendant of itself). For example: If the tree is [3,5,1,6,2,0,8,null,null,7,4], p = 5, q = 1, then the expected output is 3, because the LCA of nodes 5 and 1 is 3. If the tree is [3,5,1,6,2,0,8,null,null,7,4], p = 5, q = 4, then the expected output is 5, because the LCA of nodes 5 and 4 is 5, since a node can be a descendant of itself according to the LCA definition. If the tree is [1,2], p = 1, q = 2, then the expected output is 1. Consider these constraints: The number of nodes in the tree is in the range [2, 10^5]. -10^9 <= Node.val <= 10^9 All Node.val are unique. p != q p and q will exist in the tree.

Amazon

Design a Chess Board using Object-Oriented principles. Consider the classes, their attributes, and methods. Focus on the core components like the board, pieces, and interactions between them. For example, how would you represent the different chess pieces (pawn, rook, knight, etc.) and their unique movement rules? How would you handle the logic for checking if a move is valid, including considering piece-specific constraints and checking for checkmate or stalemate scenarios? Illustrate with code snippets to showcase how these objects would interact. How will you handle special moves like castling and en passant? How would you keep track of the game state and handle turn management?

Amazon

Describe a time when a plan did not go as expected.