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# Palindrome

Library for palindrome search


## Description

The palindrome library can test if a string is a palindrome and is able to find 
the longest palindrome within a character string.

The library is tested with an Arduino UNO, random string of 1600 characters.


## Interface

- **palindrome()** constructor.
- **int findPalindrome(const char \* str, int & position, int & length)** find the longest palindrome in a string. (first occurrence).
- **int findEvenPalindrome(const char \* str, int & position, int & length)** find the longest palindrome in a string with even length. (first occurrence).
- **int findOddPalindrome(const char \* str, int & position, int & length)** find the longest palindrome in a string with odd length. (first occurrence).
- **bool isPalindrome(const char \* str)** checks if a string is a palindrome.
- **int palindromeCount(const char \* str)** returns the count of matching pairs in a string. This is at most the ```length / 2 + 1```.
- **float palindromePercentage(const char \* str)** returns the count as percentage 0.0 .. 100.0 %


## Operation

The examples show the basic working of the functions.


## Questions

- is an empty string a palindrome?


## Future

- update documentation
- should this be a class?
- function names?
  - palindromeCount -- symmetryCount?
  - palindromePercentage -- symmetryPercentage?
- improve algorithms
  - merge odd / even find algorithms?
- investigate Print interface?
- investigate palindrome for numbers - radix 2..16 (36?)
- investigate case (in)sensitive flag?
- investigate ignore spaces flag?