Amazon Software Development Engineer II interview questions

1st Round: 1. Design Subway Suffers game. 2. what a negative feedback recently you got. 3. Describe recent challenging work done. 2nd Round: 1. Design Resource Pool 2. input a number and check if the sum of two numbers in a BST matches with it. 3 rd Round: 1. Create Doubly link list from a BST 2. given two sorted array a1 and a2 with length m+n and n , a1 has only m elements, Merge a2 to a1 so that elements are in sorted order, don't use 3rd array. 4rth Round: 1. One design question (don't remember) 2. Some Behavioral questions (don't remember) 5th Round: Didn't happen.

Q. Diameter of a tree. Q. Stack boarding passes into source and destination. Q. Design system to do a db switch.