C#

int[] list = new int[100000];
for (int i = 0; i < list.Length; i++)
   list[i] = i;

Random r = new Random();

for (int i = 0; i < 1000000; i++)
{
   int i1 = r.Next(0, list.Length);
   int i2 = r.Next(0, list.Length);
   int temp = list[i1];
   list[i1] = list[i2];
   list[i2] = temp;
}

int counter = 0;
for (int i = 0; i < list.Length; i++)
   if (i == list[i])
      counter++;

Wjousts wrote:

BTW, what's the last for loop for?

Robert Rohde wrote:

It was for myself trying to determine if one million switches would be enough. My tests mostly said that 0-2 elements were at its original position. Whether this was because they weren't hit by the algorithm or if they were just reswitched I don't know .

int[] myArray = new int[100000];
Random rnd = new Random();
ArrayList number = new ArrayList(100000);
for (int i=0; i<100000; i++)
{
    number.Add(i);
}
for (int i=0; i<100000; i++)
{
    int temp = rnd.Next(numbers.Count);
    myArray[i] = numbers[temp];
    numbers.RemoveAt(temp);
}