Data update

Task/Monty-Hall-problem/Chapel/monty-hall-problem-2.chapel

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+use Random;
+
+config const numGames = 100_000_000;
+
+var switch, stick: uint;
+
+// have a separate RNG for each task; add together the results at the end
+forall i in 1..numGames
+  with (var rand = new RandomStream(uint, parSafe = false), + reduce stick)
+{
+  var chosen_door = rand.getNext() % 3;
+  var winner_door = rand.getNext() % 3;
+  if chosen_door == winner_door then
+    stick += 1;
+}
+
+// if you lost by sticking it means you would have won by switching
+switch = numGames - stick;
+writeln("Over ", numGames, " games:\n - switching wins ",
+        100.0*switch / numGames, "% of the time and\n - sticking  wins ",
+        100.0*stick  / numGames, "% of the time");