3 random numbers into array

Question

I am writing the beginning of my program which is to have the computer generate 3 random numbers on the console.

They need to be 1-9 (including both), no numbers can repeat, and I need to put this answer into an array. What's needed in the main method class vs the class.

Why is this opinion-based? This isn't a question of whether **blue** or **red** is the **best colour for a car**. This has a very well defined question, regardless how trivial it is. — Enigmativity, Feb 14 '16 at 08:16

score 1 · Answer 1 · edited May 23 '17 at 12:15

You should try it out yourself first (site rules say so), but some hints may be provided:

1) integer random numbers can be generated using Random class. More details can be found here and an answer has been already provided about generation

2) to avoid duplicates each number should be tested against the existing list of numbers:

array.Contains(generatedNumber)

3) For your particular request, an elegant option is to generate all numbers between 1 and 9, shuffle the array and pick the first three elements:

var initArray = Enumerable.Range(1, 9).ToArray();
var randomArray = initArray.OrderBy(x => rnd.Next()).ToArray();

Get first three elements and those are random and distinct.

Generally, you can a subarray using the method specified here.

Nadimul De Cj · Answer 2 · 2016-02-14T08:13:11.733

0

Try this code below :

//range set 0 to 9
int Min = 0;
int Max = 10;

//declare an array which store 3 random number
int[] arr = new int[3]; 

Random randNum = new Random();
for (int i = 0; i < arr.Length; i++)
{
    arr[i] = randNum.Next(Min, Max);
    Console.WriteLine(arr[i]);
}

edited Feb 14 '16 at 08:13

answered Feb 14 '16 at 07:53

Nadimul De Cj

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this does not prevent duplicate values – derpirscher Feb 14 '16 at 07:56
This also never selects `9`. – Enigmativity Feb 14 '16 at 08:01
@Enigmativity ....... change the Max 9 to 10 ... – Nadimul De Cj Feb 14 '16 at 08:05
@derpirscher .... what kind of duplicate value you talking about ?? – Nadimul De Cj Feb 14 '16 at 08:10
@NadimulDeCj The original question states that _no numbers can repeat_. Your code does not prevent this (ie the same number can appear twice or even thrice in the result array) – derpirscher Feb 14 '16 at 08:21
Did you mean to reply to @derpirscher? – Enigmativity Feb 14 '16 at 08:46
oh extremely sorry for mistake .. @Enigmativity – Nadimul De Cj Feb 14 '16 at 09:34

score 0 · Answer 3 · answered Feb 14 '16 at 08:01

0

Try this:

Random rnd = new Random();
int[] arr = Enumerable.Range(0, 10).OrderBy(n => rnd.Next()).Take(3).ToArray();

foreach (var n in arr)
{
    Console.WriteLine(n);
}

answered Feb 14 '16 at 08:01

Enigmativity

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Any comment re down-vote? – Enigmativity Feb 14 '16 at 10:02

3 random numbers into array

3 Answers3