Eric Walker added 152. Maximum Product Subarray to Coding challenges involving array subsequences

Eric Walker added 673. Number of Longest Increasing Subsequence to Coding challenges involving array subsequences and Coding challenges involving dynamic programming (DP)

Eric Walker added 673. Number of Longest Increasing Subsequence and 152. Maximum Product Subarray to Coding challenges involving array subsequences, and added Coding challenges involving array subsequences to Algorithm coding challenges

Eric Walker added a number of topics to Algorithm coding challenges, and added Algorithm coding challenges to Algorithms and data structures