First, Try To Understand the Problem Statement. Second, Solve Code with Pen and Paper.
Third, Then Write code and submit in the OJ to justify test cases.
Fourth, If failed to AC then optimize your code to the better version.
Fifth, After failed in 3rd time see my solution. Understnad the logic and implement by your own.
Please, don’t just copy-paste the code. It will kill your creativity 🙂