C#. Int array vs. ArrayList vs. Dictionary

private static void TestIntArray() { int [] array = new int[1000]; for (int i = 0; i < 1000; i++) array[i] = i; } private static void TestArrayList() { ArrayList array = new ArrayList(); for (int i = 0; i < 1000; i++) array.Add(i); } // Code.... long start = DateTime.Now.Ticks; TestIntArray(); long end = DateTime.Now.Ticks; Console.WriteLine("Time with int array: {0}", end - start); long start2 = DateTime.Now.Ticks; TestArrayList(); long end2 = DateTime.Now.Ticks; Console.WriteLine("Time with ArrayList array: {0}", end2 - start2);

The result:

Time with int array: 30000 Time with ArrayList array: 10000

So, working with ArrayList is faster. Hm... If we have multidimensional array and Dictionary<int, int> the difference is even bigger:

private static void TestIntArray() { int [ , ] array = new int[1000, 1000]; int i = 0; for (int j = 0; j < 1000; j++) array[i , j] = i++; } private static void TestDictionary() { Dictionary<int, int> array = new Dictionary<int, int>(); int i = 0; for (int j = 0; j < 1000; j++) array.Add(j, i++); } Time with int array: 60000 Time with Dictionary: 10000

Interesting :)