Initial commit

vscode/Chapter11/LinqInParallel/Program.cs

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+using System.Diagnostics; // Stopwatch
+
+Write("Press ENTER to start. "); ReadLine();
+Stopwatch watch = Stopwatch.StartNew();
+
+int max = 45;
+IEnumerable<int> numbers = Enumerable.Range(start: 1, count: max);
+
+WriteLine($"Calculating Fibonacci sequence up to term {max}. Please wait...");
+
+// int[] fibonacciNumbers = numbers
+//   .Select(number => Fibonacci(number))
+//   .ToArray();
+
+int[] fibonacciNumbers = numbers.AsParallel()
+  .Select(number => Fibonacci(number))
+  .OrderBy(number => number)
+  .ToArray();
+
+watch.Stop();
+WriteLine("{0:#,##0} elapsed milliseconds.",
+  arg0: watch.ElapsedMilliseconds);
+
+Write("Results:");
+foreach (int number in fibonacciNumbers)
+{
+  Write($" {number:N0}");
+}
+
+static int Fibonacci(int term) =>
+  term switch
+  {
+    1 => 0,
+    2 => 1,
+    _ => Fibonacci(term - 1) + Fibonacci(term - 2)
+  };