Replacing nested if statements

Question

This is related to a chapter from beautiful code. And in that chapter I read about the nested ifs.

The author was talking about deeply nested if

Answer 1

Well, not directly an answer to your question since you specifically ask about switch/case statements, but here is a similar question.

Invert “if” statement to reduce nesting

This talks about replacing nested if's with guard-statements, that return early, instead of progressively checking more and more things before settling on a return value.