Class Solution

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 Details

    • Solution

      public Solution()
  • Method Details

    • rotatedDigits

      public int rotatedDigits(int n)