1056. Confusing Number

https://leetcode.com/problems/confusing-number

Description

A confusing number is a number that when rotated 180 degrees becomes a different number with each digit valid.

We can rotate digits of a number by 180 degrees to form new digits.

  • When 0, 1, 6, 8, and 9 are rotated 180 degrees, they become 0, 1, 9, 8, and 6 respectively.

  • When 2, 3, 4, 5, and 7 are rotated 180 degrees, they become invalid.

Note that after rotating a number, we can ignore leading zeros.

  • For example, after rotating 8000, we have 0008 which is considered as just 8.

Given an integer n, return true if it is a confusing number, or false otherwise.

Example 1:

**Input:** n = 6
**Output:** true
**Explanation:** We get 9 after rotating 6, 9 is a valid number, and 9 != 6.

Example 2:

**Input:** n = 89
**Output:** true
**Explanation:** We get 68 after rotating 89, 86 is a valid number and 86 != 89.

Example 3:

**Input:** n = 11
**Output:** false
**Explanation:** We get 11 after rotating 11, 11 is a valid number but the value remains the same, thus 11 is not a confusing number

Example 4:

**Input:** n = 25
**Output:** false
**Explanation:** We get an invalid number after rotating 25.

Constraints:

  • 0 <= n <= 109

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