Data commit

Task/Prime-conspiracy/C-sharp/prime-conspiracy.cs

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+using System;
+
+namespace PrimeConspiracy {
+    class Program {
+        static void Main(string[] args) {
+            const int limit = 1_000_000;
+            const int sieveLimit = 15_500_000;
+
+            int[,] buckets = new int[10, 10];
+            int prevDigit = 2;
+            bool[] notPrime = Sieve(sieveLimit);
+
+            for (int n = 3, primeCount = 1; primeCount < limit; n++) {
+                if (notPrime[n]) continue;
+
+                int digit = n % 10;
+                buckets[prevDigit, digit]++;
+                prevDigit = digit;
+                primeCount++;
+            }
+
+            for (int i = 0; i < 10; i++) {
+                for (int j = 0; j < 10; j++) {
+                    if (buckets[i, j] != 0) {
+                        Console.WriteLine("{0} -> {1}  count: {2,5:d}  frequency : {3,6:0.00%}", i, j, buckets[i, j], 1.0 * buckets[i, j] / limit);
+                    }
+                }
+            }
+        }
+
+        public static bool[] Sieve(int limit) {
+            bool[] composite = new bool[limit];
+            composite[0] = composite[1] = true;
+
+            int max = (int)Math.Sqrt(limit);
+            for (int n = 2; n <= max; n++) {
+                if (!composite[n]) {
+                    for (int k = n * n; k < limit; k += n) {
+                        composite[k] = true;
+                    }
+                }
+            }
+
+            return composite;
+        }
+    }
+}