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Shuffle part of a List

The amazing game the Cornball is about to be ported to C#.NET. A project which is a lot easier than expected. The number of hours I put down so far is barely hitting two digits and still I have reached a playable alpha version. The source will be published in parts or in its entirety when I am finished, but until then there is one small problem I would like to show that required some extra thought.

The class structure consists of Card and Deck, which inherits List<Card>. Deck has a Shuffle method which utilizes the Fisher-Yates algorithm.

public void Shuffle()
{
    Random random = new Random();
    for(int i = Count - 1; i >= 0; i--)
    {
        Swap(random.Next(i), i);
    }
}

internal void Swap(int fromIndex, int toIndex)
{
    Card temp = this[fromIndex];
    this[fromIndex] = this[toIndex];
    this[toIndex] = temp;
}

In the middle of the game, only a part of the game should be re-shuffled, which renders this method useless. Long story short, I came up with the following solution. Each card has a boolean property, IsInOrder, which specifies whether the card is in its correct place or not. To mix the incorrectly placed cards I just find the indices for them and use that as a base for the re-shuffle.

public void Reshuffle()
{
    List shuffle = new List();
    for(int i = 0; i < Count; i++)
    {
        if(!this[i].IsInOrder)
        {
            shuffle.Add(i);
        }
    }
    Random random = new Random();
    for(int i = shuffle.Count - 1; i >= 0; i--)
    {
        Swap(shuffle[random.Next(i)], shuffle[i]);
    }
}

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