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Shuffle

Shuffle an ArrayList in O(n) time (fastest possible way in theory and practice!)

Source

public static ArrayList Shuffle(this ArrayList list)
{
    var r = new Random((int)DateTime.Now.Ticks);
    for (int i = list.Count - 1; i > 0; i--)
    {
        int j = r.Next(0, i - 1);
        var e = list[i];
        list[i] = list[j];
        list[j] = e;
    }
    return list;
}

Example

ArrayList a = new ArrayList() { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
a.Shuffle();

Author: Maarten van Duren

Submitted on: 20 mrt. 2013

Language: C#

Type: System.Collections.ArrayList

Views: 5659