Tracing is an important programming skill. It helps you to read a program and accurately predict its behavior by being able to follow the control flow from the beginning of the program to the end of the program. Trace ( variable and output) the recursive function to understand the recursion better. Typing the code in a compiler and running it, defeats the purpose of this exercise. Research has shown that code tracing increases code-writing skills, both in terms of code semantics and code syntax (Kumar, 2013; Kumar, 2015 A study of the influence of code-tracing problems on code-writing skills).

For each function call, draw a separate box and put the function call in the box ( message(2), message(1)...)

Draw a separate box for the output window and clearly label it. In the output box messages are to be in the order they appear on a screen