Interview Question by Amazon
ROUND - 1
From Student A:-
1. Find the largest BST subtree in a given Binary Tree
2. Check if an array can be divided into pairs whose sum is divisible by k
From Student B:-
1. The Knight’s tour problem | Backtracking-1
From Student C:-
1. Find Second largest element in an array
2. Flatten a binary tree into linked list

ROUND - 2
From Student A:-
1. Best Time to Buy and Sell Stock
2. Median in a stream of integers (running integers)
From Student B:-
1. Previous permutation
2. Best Time to Buy and Sell Stock
2. LCA for n-ary Tree
ROUND - 3
From Student A:-
1. Uncrossed Lines
2. The Knight’s tour problem | Backtracking-1