Refactoring: words list moved to constructors

WhiteRabbit/Program.cs

@@ -21,7 +21,7 @@
             var stopwatch = new Stopwatch();
             stopwatch.Start();
 
-            var processor = new StringsProcessor("poultry outwits ants", 4);
+            var processor = new StringsProcessor("poultry outwits ants", 4, ReadInput());
             var expectedHashes = new[]
             {
                 "e4820b45d2277f3844eac66c903e84be",
@@ -31,7 +31,7 @@
 
             var expectedHashesAsVectors = new HashSet<Vector<byte>>(expectedHashes.Select(hash => new Vector<byte>(StringToByteArray(hash))));
 
-            foreach (var result in AddHashes(processor.GeneratePhrases(ReadInput())))
+            foreach (var result in AddHashes(processor.GeneratePhrases()))
             {
                 if (expectedHashesAsVectors.Contains(result.Item2))
                 {

WhiteRabbit/StringsProcessor.cs

@@ -3,16 +3,28 @@
     using System.Collections.Generic;
     using System.Collections.Immutable;
     using System.Linq;
+    using System.Numerics;
 
     internal class StringsProcessor
     {
-        public StringsProcessor(string sourceString, int maxWordsCount)
+        public StringsProcessor(string sourceString, int maxWordsCount, IEnumerable<string> words)
         {
             var filteredSource = new string(sourceString.Where(ch => ch != ' ').ToArray());
             this.VectorsConverter = new VectorsConverter(filteredSource);
+
+            // Dictionary of vectors to array of words represented by this vector
+            this.VectorsToWords = words
+                .Distinct()
+                .Select(word => new { word, vector = this.VectorsConverter.GetVector(word) })
+                .Where(tuple => tuple.vector != null)
+                .Select(tuple => new { tuple.word, vector = tuple.vector.Value })
+                .GroupBy(tuple => tuple.vector)
+                .ToDictionary(group => group.Key, group => group.Select(tuple => tuple.word).ToArray());
+
             this.VectorsProcessor = new VectorsProcessor(
                 this.VectorsConverter.GetVector(filteredSource).Value,
                 maxWordsCount,
+                this.VectorsToWords.Keys,
                 this.VectorsConverter.GetString);
         }
 
@@ -20,23 +32,16 @@
 
         private VectorsProcessor VectorsProcessor { get; }
 
-        public IEnumerable<string> GeneratePhrases(IEnumerable<string> words)
-        {
-            // Dictionary of vectors to array of words represented by this vector
-            var formattedWords = words
-                .Distinct()
-                .Select(word => new { word, vector = this.VectorsConverter.GetVector(word) })
-                .Where(tuple => tuple.vector != null)
-                .Select(tuple => new { tuple.word, vector = tuple.vector.Value })
-                .GroupBy(tuple => tuple.vector)
-                .ToDictionary(group => group.Key, group => group.Select(tuple => tuple.word).ToArray());
+        private Dictionary<Vector<byte>, string[]> VectorsToWords { get; }
 
+        public IEnumerable<string> GeneratePhrases()
+        {
             // task of finding anagrams could be reduced to the task of finding sequences of dictionary vectors with the target sum
-            var sums = this.VectorsProcessor.GenerateSequences(formattedWords.Keys);
+            var sums = this.VectorsProcessor.GenerateSequences();
 
             // converting sequences of vectors to the sequences of words...
             var anagramsWords = sums
-                .Select(sum => ImmutableStack.Create(sum.Select(vector => formattedWords[vector]).ToArray()))
+                .Select(sum => ImmutableStack.Create(sum.Select(vector => this.VectorsToWords[vector]).ToArray()))
                 .SelectMany(this.Flatten)
                 .Select(stack => stack.ToArray());
 

WhiteRabbit/VectorsProcessor.cs

@@ -9,11 +9,14 @@
 
     internal class VectorsProcessor
     {
-        public VectorsProcessor(Vector<byte> target, int maxVectorsCount, Func<Vector<byte>, string> vectorToString)
+        public VectorsProcessor(Vector<byte> target, int maxVectorsCount, IEnumerable<Vector<byte>> vectors, Func<Vector<byte>, string> vectorToString)
         {
             this.Target = target;
             this.MaxVectorsCount = maxVectorsCount;
             this.VectorToString = vectorToString;
+
+            var filteredVectors = FilterVectors(vectors, target);
+            this.Vectors = ImmutableStack.Create(filteredVectors.ToArray());
         }
 
         /// <summary>
@@ -28,16 +31,16 @@
 
         private int MaxVectorsCount { get; }
 
+        private ImmutableStack<Vector<byte>> Vectors { get; }
+
         private Func<Vector<byte>, string> VectorToString { get; }
 
         private long Iterations { get; set; } = 0;
 
         // Produces all sequences of vectors with the target sum
-        public IEnumerable<Vector<byte>[]> GenerateSequences(IEnumerable<Vector<byte>> vectors)
+        public IEnumerable<Vector<byte>[]> GenerateSequences()
         {
-            var filteredVectors = this.FilterVectors(vectors);
-            var dictionary = ImmutableStack.Create(filteredVectors.ToArray());
-            var unorderedSequences = this.GenerateUnorderedSequences(this.Target, ImmutableStack.Create<Vector<byte>>(), dictionary);
+            var unorderedSequences = this.GenerateUnorderedSequences(this.Target, ImmutableStack.Create<Vector<byte>>(), this.Vectors);
             var allSequences = unorderedSequences.SelectMany(this.GeneratePermutations);
 
             return allSequences;
@@ -48,22 +51,22 @@
         // Total number of quadruplets is reduced from 1468M to mere 311M.
         // Also, it produces the intended results faster (as these are more likely to contain longer words - e.g. "poultry outwits ants" is more likely than "p o u l t r y o u t w i t s a n t s").
         // This method basically gives us the 1-norm of the vector in the space rescaled so that the target is [1, 1, ..., 1].
-        private int GetVectorWeight(Vector<byte> vector)
+        private static int GetVectorWeight(Vector<byte> vector, Vector<byte> target)
         {
             var weight = 0;
-            for (var i = 0; this.Target[i] != 0; i++)
+            for (var i = 0; target[i] != 0; i++)
             {
-                weight += (720 * vector[i]) / this.Target[i]; // 720 = 6!, so that the result will be a whole number (unless Target[i] > 6)
+                weight += (720 * vector[i]) / target[i]; // 720 = 6!, so that the result will be a whole number (unless Target[i] > 6)
             }
 
             return weight;
         }
 
-        private IEnumerable<Vector<byte>> FilterVectors(IEnumerable<Vector<byte>> vectors)
+        private static IEnumerable<Vector<byte>> FilterVectors(IEnumerable<Vector<byte>> vectors, Vector<byte> target)
         {
             return vectors
-                .Where(vector => ((this.Target - vector) & Negative) == Vector<byte>.Zero)
-                .OrderBy(GetVectorWeight);
+                .Where(vector => ((target - vector) & Negative) == Vector<byte>.Zero)
+                .OrderBy(vector => GetVectorWeight(vector, target));
         }
 
         [Conditional("DEBUG")]