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/**

* A palindrome is any string that can be reversed and still be the same.

* An example of one is 'radar', since it is spelled the same even after

* being reversed. One method to check if a

*

* Here's how this works recursively:

*

* Palindrome('radar')

* true && Palindrome('ada')

* true && true && Palindrome('d')

* true && true && true && true

*

* @flow

* @complexity: O(n)

*/

const PalindromeRecursive = (string) => {

// Base case

if (string.length < 2) return true

// Check outermost keys

if (string[0] !== string[string.length - 1]) {

return false

}

return PalindromeRecursive(string.slice(1, string.length - 1))

}

const PalindromeIterative = (string) => {

const _string = string

.toLowerCase()

.replace(/ /g, '')

.replace(/,/g, '')

.replace(/'.'/g, '')

.replace(/:/g, '')

.split('')

// A word of only 1 character is already a palindrome, so we skip to check it

while (_string.length > 1) {

if (_string.shift() !== _string.pop()) {

return false

}

}

return true

}

export { PalindromeIterative, PalindromeRecursive }