Longest common subsequnce

Question

Please refer code below:
https://code.sololearn.com/cA45A22a19a2/#cpp
I am wondering why we are comparing from last character as equal or not? We could have compared like first character is matching or not.

Answer 1

comparing first char involves more complexity: the base case should test for end of strings reached, and the recursion should use different stribg start positions at each call ^^