Hi All :-)
I think some of you may read this problem from hackerrank. Here is the link:
https://www.hackerrank.com/challenges/dynamic-programming-classics-the-longest-common-subsequence
Since the test data is so weak, the traditional O(mn) solution can pass all the test data. So let's assume the two strings can be as long as 10^5. In this case, how to solve this problem? I guess the time complexity of the solution should be O(500*10^5) but have no idea to code it ... :-(