Resolved Stop repeat the number on my list?

Hi,
My script give me a list with random numbers but I don't want it to repeat the numbers. How to do that?

Code (CSharp):

1.  
2.     public int Rand, Lenght = 30, Picker = 1;
3.     public List<int> Randomlist = new List<int>();
4.     public bool changeNumber = true;
5.  
6.     void Start()
7.     {
8.  
9.         Randomlist = new List<int>(new int[Lenght]);
10.  
11.     }
12.  
13.     void Update()
14.     {
15.  
16.       if (t changeNumber == true)
17.         {
18.             for (int j = 1; j < Lenght; j++)
19.             {
20.                 Rand = Random.Range(0, 30);
21.                 Randomlist[j] = Rand;
22.                 Picker = 1;
23.                 changeNumber = false;
24.             }
25.  
26.         }
27. }
28.  

 

Instead of generatimg random numbers, generate first a list of numbers from 0 to 30 ( all of them).

Then use an algorithm like this to randomly shuffle the list:

https://stackoverflow.com/questions/273313/randomize-a-listt

 

Thank you for your help. I read some answers there and not all fit my simple script. Some freeze the engine !!
One of them was good but the problem is when I use bool to regenerate the numbers I double the values !! If you could solve this will be good.

Code (CSharp):

1.     List<int> xList = new List<int>() { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
2.     public List<int> deck = new List<int>();
3.  
4.     void Update()
5.     {
6.  
7.         if (changeNumber == true)
8.         {
9.             foreach (int xInt in xList)
10.             {
11.                 deck.Insert(Random.Range(0, deck.Count + 1), xInt);
12.             }
13.             changeNumber = false;
14.         }
15.     }
16.  

 

Any shuffle routine with a bug in it that does not exit will freeze the engine. This is by design.

Clear the

deck

before you go stuffing random values into it.

https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1.clear?view=net-5.0

More performant and with FAR less memory churn, just use a basic Fisher-Yates shuffle. But make it properly as the Wikipedia pseudocode shows, without bugs

https://en.wikipedia.org/wiki/Fisher–Yates_shuffle

 

Thank you Kurt, now my script run well. Here is the new scripts for people like me.

Code (CSharp):

1.     List<int> xList = new List<int>() { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
2.     public List<int> deck = new List<int>();
3.     void Update()
4.     {
5.         if (changeNumber == true)
6.         {
7.             deck.Clear();
8.             foreach (int xInt in xList)
9.             {
10.                 deck.Insert(Random.Range(0, deck.Count + 1), xInt);
11.             }
12.             changeNumber = false;
13.         }
14.     }

 

Code (CSharp):

1. // take int in, create int-length list starting at offset, randomize it
2.     public static List<int> createAndRandomizeList(int length, int offset)
3.     {
4.         List<int> tempCreateRandList = new List<int>();
5.         for (int i = 0; i < length; i++)
6.         {
7.             tempCreateRandList.Add(i + offset);
8.         }
9.  
10.         for (int i = 0; i < tempCreateRandList.Count; i++)
11.         {
12.             int temp = tempCreateRandList[i];
13.             int rand = Random.Range(i, tempCreateRandList.Count);
14.             tempCreateRandList[i] = tempCreateRandList[rand];
15.             tempCreateRandList[rand] = temp;
16.         }
17.         //Debug.Log("tempCreateRandList = " + string.Join(",", tempCreateRandList));
18.         return tempCreateRandList;
19.     }