Generating random values in Swift between two integer values

Question

I'm trying to generate random values between two integers. I've tried this, which starts from 0,

let randomNumber = arc4random_uniform(10)
println(randomNumber)

But I need a value between 10 and 50.

score 67 · Accepted Answer · answered Jun 17 '14 at 05:51

67

try this

let randomNumber = arc4random_uniform(40) + 10
println(randomNumber)

in general form

let lower : UInt32 = 10
let upper : UInt32 = 50
let randomNumber = arc4random_uniform(upper - lower) + lower
println(randomNumber)

answered Jun 17 '14 at 05:51

Bryan Chen

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3

add one to `upper - lower` in order to allow 50 as possible result here (since `arc4random_uniform(40)` will return integers in the range 0 -to- 39) – fqdn Jun 17 '14 at 05:58
1

@ackStOverflow that depends OP want `1..50` or `1...50` – Bryan Chen Jun 17 '14 at 06:01

Chris · Answer 2 · 2019-11-25T22:13:06.817

41

This is an option for Swift 4.2 and above using the random() method, which makes it easy!

let randomInt = Int.random(in: 10...50)

The range can be a closed (a...b) or half open (a..<b) range.

edited Nov 25 '19 at 22:13

answered May 31 '18 at 20:25

Chris

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score 10 · Answer 3 · edited Apr 25 '18 at 19:01

10

If you want a reusable function with simple parameters:

func generateRandomNumber(min: Int, max: Int) -> Int {
    let randomNum = Int(arc4random_uniform(UInt32(max) - UInt32(min)) + UInt32(min))
    return randomNum
}

edited Apr 25 '18 at 19:01

esreli

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38

answered Aug 29 '16 at 22:29

mattgabor

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score 2 · Answer 4 · answered May 31 '18 at 19:08

2

more simple way of random number generator

func random(min: Int, max: Int) -> Int {
    return Int(arc4random_uniform(UInt32(max - min + 1))) + min
}

answered May 31 '18 at 19:08

Rizwan Mehboob

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16
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Generating random values in Swift between two integer values

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