## 题目描述：

LeetCode 788. Rotated Digits

X is a good number if after rotating each digit individually by 180 degrees, we get a valid number that is different from X. A number is valid if each digit remains a digit after rotation. 0, 1, and 8 rotate to themselves; 2 and 5 rotate to each other; 6 and 9 rotate to each other, and the rest of the numbers do not rotate to any other number.

Now given a positive number `N`, how many numbers X from `1` to `N` are good?

```Example:
Input: 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.
```

Note:

• N  will be in range `[1, 10000]`.

## Python代码：

``````class Solution(object):
def rotatedDigits(self, N):
"""
:type N: int
:rtype: int
"""
ans = 0
for n in range(1, N + 1):
nset = set(map(int, str(n)))
if any(x in nset for x in (2, 5, 6, 9)):
if not any(x in nset for x in (3, 4, 7)):
ans += 1
return ans
``````

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