Hello cf community, I always get stuck at finding patterns if I have to create them from scratch, but other constructive problems around similar or even higher levels i can solve easily..

Eg of what I'm talking about:

https://www.codechef.com/problems/GRIDEVEN

Maybe i would feel much more confident and improve my intuition if I can solve similar problems, so please share if you have any construction-based problems that you feel is nice and tough!