# Iteration And Recursion Homework Help

## Recursion Defined

Recursion is a way of determining information data structures or algorithms in terms of themselves. A recursive algorithm is a form of decomposition where rather than selecting an arbitrary subtask of the issue to do, select a simpler problem that has the same form as the original (self-similarity). A recursive description has two parts:

- The
**base case**- a stopping condition - The
**recursive step**- an expression of the calculation or definition in terms of itself

### Example of a Recursive Definition:

- There are many recursive definitions in mathematics. Consider the factorial function:
- n! = n * (n-1) * (n -2) * … * 2 * 1

- The same function can be defined recursively by giving a base case and a recursive step:
- 0! = 1 (by definition)
- n! = n * (n - 1)! (the recursive step)