Can anyone give me some tips about solving constructives quickly on codeforces pls? Now what I'm doing is smth like random guessing (I cannot find the right method quick often), and if I failed, I get stuck on that problem for a long time!

Example: In Codeforces Round 953 (Div. 2) I get stuck on C (constructive) for about 40min and therefore get a low ranking(although I solved D and E fast). This kind of things often happens on me and that's kinda annoying.

Sorry for poor English. Any help will be appreciated.