You should aim for a solution as good or better than O(m * n) time and O(m * n) space, where m is the length of the string text1 and n is the length of the string text2.

Try to think in terms of recursion and visualize it as a decision tree. Can you determine the possible decisions at each step? Maybe you should consider iterating through both strings recursively at the same time.

At each recursion step, we have two choices: if the characters at the current indices of both strings match, we move both indices forward and extend the subsequence. Otherwise, we explore two paths by advancing one index at a time and recursively finding the longest subsequence. We return the maximum length between these two choices. This approach is exponential. Can you think of a way to optimize it?

We return 0 if either index goes out of bounds. To optimize, we can use memoization to cache recursive call results and avoid redundant calculations. A hash map or a 2D array can be used to store these results.