How to arrange N queens in O(N) time
How to efficiently solve the N Queens problem with a staircase pattern arrangement if you just need one solution.

How to efficiently solve the N Queens problem with a staircase pattern arrangement if you just need one solution.
A solution for a tricky Tricky OA problem related to clustering
Solving the Leetcode 24 Game by precomputing the results in a relatively small associative array, although it is marked as a HARD problem.
A clever logarithmical solution for Leetcode Pens and Pencils problem