Medium Top Interview set 2

Question 1

Tic Tac Toe

Answer 1

Create board. For every move, check row, col and diagonals. Both diagonals.

Question 2

378. Kth Smallest element in a sorted matrix

Answer 2

Use a heap, pop the smallest and push its neighbours.

Question 3

384 Shuffle an array

Answer 3

Generate random number j from n to 0 and keep shuffling

Question 4

Kth Largest element in an array

Answer 4

heapify

Question 5

Group anagrams

Answer 5

dictionary of sorted strings

Question 6

62 unique paths

Answer 6

Dynamic programming

Question 7

11. Container with most water

Answer 7

Two pointer approach from extreme ends

Question 8

380 Insert delete getrandom

Answer 8

Keep a list and a dictionary