Find the minimum number of operations needed to transform an array or string into some rotation that is a palindrome.
You are given a sequence of values. In one operation, you may change an element so that the sequence can be rearranged through rotation into a palindrome. Determine the minimum number of changes required to make some cyclic rotation of the sequence a palindrome.
A rotation chooses a starting position and reads the sequence circularly from that point. The goal is to perform the fewest modifications so that at least one rotation becomes a palindrome.
Input Format
- A sequence of length represented as an array or string.
- You may assume the sequence is finite and indexable.
- The exact input encoding depends on the platform wrapper.
Output Format
- Return a single integer: the minimum number of modifications needed so that some rotation of the sequence is a palindrome.
Constraints
- The sequence length is positive.
- A palindrome reads the same forward and backward.
- A rotation uses the sequence cyclically; no elements are removed or reordered beyond choosing the start position.
- Exact platform constraints are not provided in the source metadata.
Example 1
Input
s = "aabca"
Output
1
Explanation
One change can make a rotation palindromic, for example by changing one character so that an appropriate cyclic shift reads the same forward and backward.
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