“Necessary” Uses of Recursion in Imperative Languages

Question

I\'ve recently seen in a couple of different places comments along the lines of, \"I learned about recursion in school, but have never used it or felt the need for it since

Answer 1

In my work recursion is very rarely used for anything algorithmic. Things like factorials etc are solved much more readably (and efficiently) using simple loops. When it does show up it is usually because you are processing some data that is recursive in nature. For example, the nodes on a tree structure could be processed recursively.

If you were to write a program to walk the nodes of a binary tree for example, you could write a function that processed one node, and called itself to process each of it's children. This would be more effective than trying to maintain all the different states for each child node as you looped through them.