788. Rotated Digits Medium

1/**
2 * [788] Rotated Digits
3 *
4 * 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.
5 * A number is valid if each digit remains a digit after rotation. For example:
6 * 
7 * 	0, 1, and 8 rotate to themselves,
8 * 	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),
9 * 	6 and 9 rotate to each other, and
10 * 	the rest of the numbers do not rotate to any other number and become invalid.
11 * 
12 * Given an integer n, return the number of good integers in the range [1, n].
13 *  
14 * Example 1:
15 * 
16 * Input: n = 10
17 * Output: 4
18 * Explanation: There are four good numbers in the range [1, 10] : 2, 5, 6, 9.
19 * Note that 1 and 10 are not good numbers, since they remain unchanged after rotating.
20 * 
21 * Example 2:
22 * 
23 * Input: n = 1
24 * Output: 0
25 * 
26 * Example 3:
27 * 
28 * Input: n = 2
29 * Output: 1
30 * 
31 *  
32 * Constraints:
33 * 
34 * 	1 <= n <= 10^4
35 * 
36 */
37pub struct Solution {}
38
39// problem: https://leetcode.com/problems/rotated-digits/
40// discuss: https://leetcode.com/problems/rotated-digits/discuss/?currentPage=1&orderBy=most_votes&query=
41
42// submission codes start here
43
44impl Solution {
45    pub fn rotated_digits(n: i32) -> i32 {
46        0
47    }
48}
49
50// submission codes end
51
52#[cfg(test)]
53mod tests {
54    use super::*;
55
56    #[test]
57    fn test_788() {
58    }
59}
60