### Problem Statement

You are going to stick the number of your room on the door. The shop near your house suggests wonderful sets of plastic digits. Each set contains exactly ten digits - one of each digit between 0 and 9, inclusive. Return the number of sets required to write your room number. Note that 6 can be used as 9 and vice versa.

### Definition

 Class: RoomNumber Method: numberOfSets Parameters: int Returns: int Method signature: int numberOfSets(int roomNumber) (be sure your method is public)

### Constraints

-roomNumber will be between 1 and 1,000,000, inclusive.

### Examples

0)

 `122`
`Returns: 2`
 Two sets are required because each set contains only one '2' digit.
1)

 `9999`
`Returns: 2`
 Each set contains one '6' digit and one '9' digit. '6' could be used as '9' and therefore two sets are enough.
2)

 `12635`
`Returns: 1`
3)

 `888888`
`Returns: 6`

#### Problem url:

http://www.topcoder.com/stat?c=problem_statement&pm=6764

#### Problem stats url:

http://www.topcoder.com/tc?module=ProblemDetail&rd=10675&pm=6764

Andrew_Lazarev

#### Testers:

PabloGilberto , brett1479 , Olexiy

#### Problem categories:

Simple Math, String Manipulation