Solution (leetcode-in-java 1.23 API)

java.lang.Object
- g0701_0800.s0788_rotated_digits.Solution

```
public class Solution
extends Object
```
788 - Rotated Digits.
Medium

An integer x is a good if after rotating each digit individually by 180 degrees, we get a valid number that is different from x. Each digit must be rotated - we cannot choose to leave it alone.

A number is valid if each digit remains a digit after rotation. For example:
- 0, 1, and 8 rotate to themselves,
- 2 and 5 rotate to each other (in this case they are rotated in a different direction, in other words, 2 or 5 gets mirrored),
- 6 and 9 rotate to each other, and
- the rest of the numbers do not rotate to any other number and become invalid.
Given an integer n, return the number of good integers in the range [1, n].

Example 1:

Input: n = 10

Output: 4

Explanation:
```
 There are four good numbers in the range [1, 10] : 2, 5, 6, 9.
 Note that 1 and 10 are not good numbers, since they remain unchanged after rotating. 
```
Example 2:

Input: n = 1

Output: 0

Example 3:

Input: n = 2

Output: 1

Constraints:
- 1 <= n <= 10⁴

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  int rotatedDigits(int n)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution()
```

Method Detail
- rotatedDigits
```
public int rotatedDigits(int n)
```