C#

Quote:

Every number will be the first in the sequence based on the supplied seed. If you call it twice with the same seed (i.e. within one tick) you will get the same number.

private static Random rndNumber = new Random();
public static void Shuffle(int[] a)
{
    int n = a.Length;
    ...

    int[] a = new int[arraySize];
    //Fill the array with unique values
    for (int i = 0; i < a.Length; i++)
        {
        a[i] = i + 1;
        }
    int[] b = Shuffle(a).ToArray();
    Console.WriteLine("\nThe array will now be displayed\n");
    foreach (int i in b)
        {
        Console.WriteLine(i);
        }
    }
private static Random rndNumber = new Random();
public static IEnumerable<T> Shuffle<T>(IEnumerable<T> a)
    {
    int values = a.Count();
    List<T> output = new List<T>(values);
    List<T> input = a.ToList();
    for (int index = 0; index < values; index++)
        {
        int i = rndNumber.Next(0, input.Count());
        output.Add(input[i]);
        input.RemoveAt(i);
        }
    return output;
    }

OriginalGriff wrote:

your Random.Next call can't return zero

OriginalGriff wrote:

does this make any sense to you?

private Random newRandom = new Random();

private List<int> MakeShuffledList1(int nItems)
{
    return Enumerable.Range(1, nItems).ToList().OrderBy(item => newRandom.Next()).ToList();
}

// test
List<int> newList = MakeShuffledList1(10);

// if thread safety is not an issue: make static ?
private Random newRandom = new Random();

private List<int> MakeShuffledList2(int nItems)
{
    List<int> shuffleList = Enumerable.Range(1, nItems).ToList();
    
    List<int> resultList = new List<int>();
    
    int currentValue;
    
    while (shuffleList.Count > 0)
    {
        currentValue = shuffleList[newRandom.Next(0, shuffleList.Count - 1)];
        resultList.Add(currentValue);
        shuffleList.Remove(currentValue);
    }
    
    return resultList;
}

List<List<int>> bunchOLists = new List<List<int>>();

for (int i = 0; i < 10; i++)
{
    bunchOLists.Add(MakeShuffledList1(5));
    bunchOLists.Add(MakeShuffledList2(5));
}

// test

bool IsDuplicate = false;

List<int> currentList;

for (int i = 0; i < bunchOLists.Count - 1; i++)
{
    currentList = bunchOLists[i];

    for (int j = 0; j < bunchOLists.Count - 1; j++)
    {
        if(i != j)
        {
            IsDuplicate = currentList.SequenceEqual(bunchOLists[j]);
        }
    }
}

Console.WriteLine("all List<int> are unique: " + (! IsDuplicate).ToString());

emma.sun.sts wrote:

So I included Microsoft.Vbe.Interop in References

Member 10527273 wrote:

so please help me