Ben's Code Challenge 2018-11-13

// I did this the hard way and it would have been a lot
// easier to do it using this Hint:
// Hint: In order for a word to be a palindrome, is needs to have an even amount of the same letters on each side with the exception of a single letter in the middle

// pseudo code of easier way:
// for each letter in the string
// save it to a key pair array
// key being letter
// pair being count
// if all key pairs have even values
// then it can be a palindrome
// if all but one are even then it can be a palindrome
// if two are odd then not

import UIKit
import Foundation

var str = "Hello, playground"

func canBePalindrome(_ str: String){
    //
    
    // get string into set of strings
    var subString : Character
    var subStringArray : [String] = []
    var index : Int = 0
    for index in 0..<str.count {
        let temp = str.index (str.startIndex, offsetBy: index)
        subString = str[temp]
        subStringArray.append(String(subString))
        
    }
    
    print(subStringArray)
    
    
    // build the possible strings
    
    
    // call palindromeChecker(_ strArray : [String]) on possible strings
    // if return return false, continue, until then end and return false/
    // if return true, early return true.
}
   // for char in str


canBePalindrome("carrace")

// palindrome checker
func palindromeChecker(_ strArray : [String])->String{
    
    var tail: Int = 0
    var head: Int = strArray.count - 1
    while (head > tail) {
        
        if(strArray[head] == strArray[tail]){
            head -= 1
            tail += 1
            continue
        }
        else { return "false"}
    }
    return "true"
}


func permuteWirth<T>(_ a: [T], _ n: Int) {
    if n == 0 {
        print(a)   // display the current permutation
    } else {
        var a = a
        permuteWirth(a, n - 1)
        for i in 0..<n {
            a.swapAt(i, n)
            permuteWirth(a, n - 1)
            a.swapAt(i, n)
        }
    }
}

var testPalindrome: [String] = ["a","b","b"]

let result = palindromeChecker(testPalindrome)

print(result)