2 using System.Collections.Generic;
6 // Tests whether group i by i is optimized
10 public static int Main ()
12 int[] int_array = new int [] { 0, 1, 2, 3, 4 };
14 var e = from i in int_array group i by i;
17 foreach (var ig in e) {
18 Console.WriteLine (ig.Key);
23 Console.WriteLine ("OK");