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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static void Main()
	{
		int match = 0;
		int fail = 0;
		int windowHit = 0;
		
		for (int i=0; i<32; i++) {
			int tick = Environment.TickCount;
			var r1 = new Random();
			var r2 = new Random();
			int tickClose = Environment.TickCount;
			
			if (tick == tickClose) { 
				// both r1 and r2 seeded during same Enviroment.tickCount window
				windowHit++;
			}
			
			if (r1.Next() == r2.Next()) {
				match++;
			} else {
				fail++;
			}
		}
		
		Console.WriteLine($"Hit Environment.TickCount window {windowHit} times");
		Console.WriteLine($"Collisions: {match}");
		Console.WriteLine($"Unique first elements: {fail}");

	}
}