Practice Rotated Digits
Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.
Problem Statement
Count integers from 1 through n that change to a different valid number when every digit is rotated individually. Digits 0, 1 and 8 stay unchanged; 2 and 5 swap; 6 and 9 swap; 3, 4 and 7 are invalid. Keep the digit order. A number qualifies only if all digits are valid and at least one changes.
Source: Rotated Digits on LeetCode. Use the original task for its coding environment and submissions.
Examples
# Example 1
Input
n = 10
Output
4
# Example 2
Input
n = 1
Output
0
# Example 3
Input
n = 2
Output
1
Constraints
1 <= n <= 10^4
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