how do i slove a problem like this?

Question

what's the easiest way to solve coding problems/ questions about filling in the missing code?

Answer 1

Google with a mix of trial and error

Answer 2

Step by Step
Take small steps
Take steps in the right order to begin with the first step.

It sound really easy, but I have learned it the hard way. I do still notice that if I cannot solve the problem, I have to admit that I probably broke one of the rules above.