feat(2015-04): Add day 4 solution

2026-07-13 19:23:46 +00:00 · 2022-10-13 13:07:49 +01:00
parent 53330a4f5d
commit 6ea37b30d4
3 changed files with 89 additions and 0 deletions
@@ -0,0 +1,78 @@
+using System.Reflection;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace AOC.Tests.Y2015
+{
+    [TestFixture, Parallelizable(ParallelScope.All)]
+    public class Day04
+    {
+        protected string GetThisClassName() { return this.GetType().Name; }
+        private string realData;
+
+        [SetUp]
+        public void Setup()
+        {
+            realData = File.ReadAllLines(Path.Combine(TestContext.CurrentContext.TestDirectory, "Y2015", "Data", $"{GetThisClassName()}.dat"))[0];
+        }
+
+        private int CreateMD5Hash(string input, string startingString)
+        {
+            int result = 0;
+
+            MD5 md5 = MD5.Create();
+
+            while (true)
+            {
+                byte[] inputBytes = new UTF8Encoding().GetBytes($"{input}{result}");
+                byte[] hashBytes = md5.ComputeHash(inputBytes);
+                StringBuilder sb = new StringBuilder();
+                foreach (var t in hashBytes)
+                {
+                    sb.Append(t.ToString("X2"));
+                }
+
+                if (sb.ToString().StartsWith(startingString))
+                {
+                    break;
+                }
+
+                result += 1;
+            }
+
+            return result;
+        }
+
+        [TestCase("abcdef", 609043)]
+        [TestCase("pqrstuv", 1048970)]
+        [TestCase(null, 254575)] // The actual answer
+        public void Part1(string input, int? expected)
+        {
+            string lines = input != null ? input : realData;
+
+            var i = CreateMD5Hash(lines, "00000");
+
+            if (expected != null)
+            {
+                Assert.That(i, Is.EqualTo(expected.Value));
+            }
+
+            Console.WriteLine($"Part 1: {i}");
+        }
+
+        [TestCase(null, 1038736)] // The actual answer
+        public void Part2(string input, int? expected)
+        {
+            string lines = input != null ? input : realData;
+
+            var i = CreateMD5Hash(lines, "000000");
+
+            if (expected != null)
+            {
+                Assert.That(i, Is.EqualTo(expected.Value));
+            }
+
+            Console.WriteLine($"Part 2: {i}");
+        }
+    }
+}