### Problem Statement

Given a number x, we can define p(x) as the product of the digits of x. We can then form a sequence x, p(x), p(p(x))... The persistence of x is then defined as the index (0-based) of the first single digit number in the sequence. For example, using 99, we get the sequence 99, 9*9 = 81, 8*1 = 8. Thus, the persistence of 99 is 2. You will be given n, and you must return its persistence.

### Definition

 Class: PersistentNumber Method: getPersistence Parameters: int Returns: int Method signature: int getPersistence(int n) (be sure your method is public)

### Constraints

-n will be between 0 and 2,000,000,000, inclusive.

### Examples

0)

 `99`
`Returns: 2`
 The example from the problem statement.
1)

 `268`
`Returns: 4`
 The sequence here is 268, 96, 54, 20, 0.
2)

 `6`
`Returns: 0`
 6 is already a single-digit number.
3)

 `68889789`
`Returns: 3`
4)

 `86898`
`Returns: 7`

#### Problem url:

http://www.topcoder.com/stat?c=problem_statement&pm=7533

#### Problem stats url:

http://www.topcoder.com/tc?module=ProblemDetail&rd=10667&pm=7533

connect4

#### Testers:

PabloGilberto , brett1479 , Olexiy , lovro

#### Problem categories:

Simple Search, Iteration