Contents.swift

//: Playground - noun: a place where people can play

import UIKit

var str = "Hello, playground"


/*

Question 1: https://www.hackerrank.com/challenges/minimum-draws

Copy and paste your code:

What is the big O runtime of your code?:

Question 2: https://www.hackerrank.com/challenges/handshake

Copy and paste your code:

What is the big O runtime of your code?:

Question 3: https://www.hackerrank.com/challenges/connecting-towns

Copy and paste your code:

What is the big O runtime of your code?:

*/


//1. The number of draws he makes in the worst case scenario is 3. I don't know how to express that in code.

//2.


func factorial(var value: Int, var result: Int = 1) -> Int {
    
    if (value == 0) {
        return result
    }
    
    result *= value
    value--
    
    return factorial(value, result: result)
}

func handshakes(attendees: Int) -> Int {
    
    let num = factorial(attendees)
    
    let den = (factorial(2) * factorial(attendees - 2))
    
    let total = num / den
    
    return total
    
}


handshakes(4)
handshakes(2)

//3.
func gandalfsRoute(routes: Int, towns: Int) ->Int {
    let num = factorial(routes)
    let den = factorial(routes - towns)
    
    let total = num / den
    
    return total
    
}

gandalfsRoute(2, towns: 2)
gandalfsRoute(3, towns: 2)