For a question like this: public static void doSomething(int n){ if (n > 0){ doSomething(n-1); System.out.print(n * 2); doSomething(n-1); } } The problem may ask something like what this code will output if you call doSomething(5). I'm learning recursion right now, and I find it really hard tracing the execution of these questions. Are there any techniques on doing these questions? ...