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iOS

alec apter
alec apter
929 Points
Posted by alec apter
alec apter
929 Points

Help with Custom Random Number Generator

Hey guys, I was wondering if anyone could help me create a random # generator in swift that doesn't repeat the number it just generated n times. Thanks in advance.

1 Answer

Chris Stromberg
PLUS
Chris Stromberg
Courses Plus Student 13,389 Points
Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points 
import UIKit
import GameKit

enum randomRepeatError : Error {
    case invalidRepeatNumber(description: String)
}

class NumberGenerator {

    var numbersGeneratedArray: [Int] = [Int]()

    func randomNumberNotRepeated(_ times: Int) throws -> Int {

        guard  times >= 1 && times <= 100 else {
            print("!!!ERROR!!! Enter a number greater than 1 and less than 100")
            throw
                randomRepeatError.invalidRepeatNumber(description: "Enter a number greater than 1.")
                        }


        var randomNumberToReturn : Int = 0

        func makeRandomNumber() -> Int {
            return GKRandomSource.sharedRandom().nextInt(upperBound: 100)
        }

        var randomNumber: Int = 0

        var arrayContainsRandomNumber: Bool {
            return numbersGeneratedArray.contains(randomNumber)
        }

         randomNumber = makeRandomNumber()

        if numbersGeneratedArray.count >= times {
            numbersGeneratedArray.remove(at: 0)
            }


        if arrayContainsRandomNumber == true {
            randomNumber = makeRandomNumber()

                repeat { randomNumber = makeRandomNumber() }
                while numbersGeneratedArray.contains(randomNumber)

                numbersGeneratedArray.append(randomNumber)
                randomNumberToReturn = randomNumber
            }

        if arrayContainsRandomNumber == false {
            numbersGeneratedArray.append(randomNumber)
            randomNumberToReturn = randomNumber
            randomNumber = makeRandomNumber()

      }


        print("********************************************)")
        print(numbersGeneratedArray)
        print("The random number is: \(randomNumberToReturn)")


        return randomNumberToReturn

    }

}

Using the randomNumberNotRepeated function...

var number = NumberGenerator()


for i in 1...20 {
   try number.randomNumberNotRepeated(15)
}