Data commit

Task/Cuban-primes/C-sharp/cuban-primes.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+static class Program
+{
+    static List<long> primes = new List<long>() { 3, 5 };
+
+     static void Main(string[] args)
+    {
+        const int cutOff = 200;
+        const int bigUn = 100000;
+        const int chunks = 50;
+        const int little = bigUn / chunks;
+        const string tn = " cuban prime";
+        Console.WriteLine("The first {0:n0}{1}s:", cutOff, tn);
+        int c = 0;
+        bool showEach = true;
+        long u = 0, v = 1;
+        DateTime st = DateTime.Now;
+        for (long i = 1; i <= long.MaxValue; i++)
+        {
+            bool found = false;
+            int mx = System.Convert.ToInt32(Math.Ceiling(Math.Sqrt(v += (u += 6))));
+            foreach (long item in primes)
+            {
+                if (item > mx) break;
+                if (v % item == 0) { found = true; break; }
+            }
+            if (!found)
+            {
+                c += 1; if (showEach)
+                {
+                    for (var z = primes.Last() + 2; z <= v - 2; z += 2)
+                    {
+                        bool fnd = false;
+                        foreach (long item in primes)
+                        {
+                            if (item > mx) break;
+                            if (z % item == 0) { fnd = true; break; }
+                        }
+                        if (!fnd) primes.Add(z);
+                    }
+                    primes.Add(v); Console.Write("{0,11:n0}", v);
+                    if (c % 10 == 0) Console.WriteLine();
+                    if (c == cutOff)
+                    {
+                        showEach = false;
+                        Console.Write("\nProgress to the {0:n0}th{1}: ", bigUn, tn);
+                    }
+                }
+                if (c % little == 0) { Console.Write("."); if (c == bigUn) break; }
+            }
+        }
+        Console.WriteLine("\nThe {1:n0}th{2} is {0,17:n0}", v, c, tn);
+        Console.WriteLine("Computation time was {0} seconds", (DateTime.Now - st).TotalSeconds);
+        if (System.Diagnostics.Debugger.IsAttached) Console.ReadKey();
+    }
+}