**Round 1:**

1> given a number, and an encoding technique like 1-> A, 2-> C…. 26->Z, How may different valid encryption can be done. Like 123 can be decoded as ABC or LC or AW. so the count is 3

2> given an array of -1, 0, 1 in an unsorted matter. sort it in order of n time conplexity

3> How to get the top 10 occurring words from a file which is dynamically changing

**Round 2:**

1> traverse a tree in spiral order.

2> traverse a tree in spiral order using a stack and a queue

3> given a string in form of a linked link. check if it is palindrome or not .

**Round 3:**

1> Given an array which contains value in range 0 to N^2. sort it in order of N time complexity.

2> Find the largest monotonically increasing subsequence.

3> Given a binary tree, check if it is a binary search tree or not.

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