Load random scenes without repetition using c#

问题

I want to load scenes randomly without repetition using c#. Any help would do. Thanks.

int[] array = new int[] { 1, 2, 3, 4, 6, 8, 9, 10, 11, 12 };
List<int> list = new List<int>();

void Start()
{
    list.AddRange(array);
}

int GetUniqueRandom(bool RemoveFromTheList)
{
    if (list.Count == 0)
    {
        if (RemoveFromTheList)
        {
            list.AddRange(array);
        }
        else
        {
            return -1; // never repeat
        }
    }

    int rand = Random.Range(0, 10);
    int value = list[rand];
    list.RemoveAt(rand); return value;
}

回答1:

A nice clean way is to shuffle the array, then put all the elements in a stack. All you need to get a random element is to pop an item off the stack.

You will want to remove the list in the list of fields and replace with this;

Stack remainingScenes = new Stack();

Remove the content of the Start() method - you don't need it.

In your method to get a new number;

if (remainingScenes.Count == 0) {
    int n = array.Length;
        while (n > 1) 
        {
            int k = rng.Next(n--);
            T temp = array[n];
            array[n] = array[k];
            array[k] = temp;
        }

        foreach(var element in array) { 
             remainingScenes.Push(element);
        }
}

return remainingScenes.Pop();

The shuffle method is from here.

回答2:

Uhmmm, this looks very straightforward. Judging from your code, you only need a little modification to make it work..

List<int> list = new List<int>() { 1, 2, 3, 4, 6, 8, 9, 10, 11, 12 };

int GetUniqueRandom(bool RemoveFromTheList)
{
    if (list.Count == 0)
    {
        return -1;//nothing in the list so return negative value
    }
    //generate random index from list
    int randIndex = Random.Range(0, list.Count - 1);
    int value = list[rand];
    if(RemoveFromTheList)
    {
        list.RemoveAt(randIndex);
    }
    return value;
}

回答3:

Try this:

int[] array = new int[] { 1, 2, 3, 4, 6, 8, 9, 10, 11, 12 };
Stack<int> stack = null;

Then initialize like this:

var rnd = new Random();
stack = new Stack<int>(array.OrderBy(x => rnd.Next()));

Now you just keep getting values from the stack until it is empty:

var value = stack.Pop();

来源：https://stackoverflow.com/questions/38940689/load-random-scenes-without-repetition-using-c-sharp

标签

arrays

random

scene