what happens when it prints the list, how is it entering any of the loops after that?
What happens when openB=closeB==n; which if condition does it go to?
After printing the list, control goes back to the line where the function was called since recursion uses something called a call stack.
You can try to code a much simpler problem like calculating factorial of a number using recursion to get to know how call stack works.
If any doubts feel free to ask 