Chapter 1, Building Abstractions with Procedures
Section - Procedures and the Processes They Generate
Exercise 1.14
Too lazy to draw :)
We can see by looking at the procedure that space complexity is $\theta (n)$ as the deepest path of the tree can have at max $n$ nodes.
I am not able to solve for time complexity. Although we can easily see that time complexity will always be less than $2^n$ as each step is divides into two branches and the maximum depth of the tree will be $n$.
Please help, if you have solution for it.