/// <summary>
/// takes about 18 seconds on this puny laptop for 500.000 words
/// </summary>
/// <param name="words"></param>
/// <returns></returns>
public static CharDictionaryEntry LoadWords(IEnumerable<string> words)
{
var root = new CharDictionaryEntry("", false);
foreach (var word in words)
{
if (word.Length > 3)
root.AddWordTail(word.ToLower());
}
return root;
}
/// <summary>
/// takes ~1 second, depending on chars
/// </summary>
/// <param name="words">All the words</param>
/// <param name="chars">The distinct chars in the boggle field</param>
/// <returns>a dictionary with words which consist of chars</returns>
public static CharDictionaryEntry LoadWords(IEnumerable<string> words, HashSet<char> chars)
{
var root = new CharDictionaryEntry("", false);
foreach (var word in words)
{
var theword = word.ToLower();
if (word.Length > 3 && theword.All(chars.Contains))
root.AddWordTail(theword);
}
return root;
}
/// <summary>
/// takes about 18 seconds on this puny laptop for 500.000 words
/// </summary>
/// <param name="words"></param>
/// <returns></returns>
public static CharDictionaryEntry LoadWords(IEnumerable <string> words)
{
var root = new CharDictionaryEntry("", false);
foreach (var word in words)
{
if (word.Length > 3)
{
root.AddWordTail(word.ToLower());
}
}
return(root);
}
/// <summary>
/// takes ~1 second, depending on chars
/// </summary>
/// <param name="words">All the words</param>
/// <param name="chars">The distinct chars in the boggle field</param>
/// <returns>a dictionary with words which consist of chars</returns>
public static CharDictionaryEntry LoadWords(IEnumerable <string> words, HashSet <char> chars)
{
var root = new CharDictionaryEntry("", false);
foreach (var word in words)
{
var theword = word.ToLower();
if (word.Length > 3 && theword.All(chars.Contains))
{
root.AddWordTail(theword);
}
}
return(root);
}
/// <summary>
/// Creates entries for all characters in tail and adds them to this entry.
/// </summary>
/// <param name="tail"></param>
public void AddWordTail(string tail)
{
CharDictionaryEntry nextChar = this[tail[0]];
var nextIsWord = tail.Length == 1;
if (nextChar == null)
{
nextChar = new CharDictionaryEntry(Word + tail[0], nextIsWord);
this[tail[0]] = nextChar;
}
if (!nextIsWord) //more chars left
{
nextChar.AddWordTail(tail.Substring(1)); // consume 1 char and recurse
}
}
/// <summary>
/// Creates entries for all characters in tail and adds them to this entry.
/// </summary>
/// <param name="tail"></param>
public void AddWordTail(string tail)
{
CharDictionaryEntry nextChar = this[tail[0]];
var nextIsWord = tail.Length == 1;
if (nextChar == null)
{
nextChar = new CharDictionaryEntry(Word + tail[0], nextIsWord);
this[tail[0]] = nextChar;
}
if (!nextIsWord) //more chars left
{
nextChar.AddWordTail(tail.Substring(1)); // consume 1 char and recurse
}
}
/// <summary>
/// Finds all words in dictionary that are in the char field
/// </summary>
/// <param name="chars"></param>
/// <param name="dictionary"></param>
/// <returns></returns>
public static IEnumerable<BoggleSolution> FindWords(char[,] chars, CharDictionaryEntry dictionary)
{
for (int x = 0; x < chars.GetLength(0); x++)
for (int y = 0; y < chars.GetLength(1); y++)
{
foreach (var word in FindWords(
chars,
new bool[chars.GetLength(0), chars.GetLength(1)],
dictionary,
new Stack<Point>(),
x,
y
))
yield return word;
}
}
/// <summary>
/// Finds all words in dictionary that are in the char field
/// </summary>
/// <param name="chars"></param>
/// <param name="dictionary"></param>
/// <returns></returns>
public static IEnumerable <BoggleSolution> FindWords(char[,] chars, CharDictionaryEntry dictionary)
{
for (int x = 0; x < chars.GetLength(0); x++)
{
for (int y = 0; y < chars.GetLength(1); y++)
{
foreach (var word in FindWords(
chars,
new bool[chars.GetLength(0), chars.GetLength(1)],
dictionary,
new Stack <Point>(),
x,
y
))
{
yield return(word);
}
}
}
}
private static IEnumerable<BoggleSolution> FindWords(char[,] chars, bool[,] visited, CharDictionaryEntry lastStep, Stack<Point> path, int x, int y)
{
if (x < 0 || y < 0 || x >= chars.GetLength(0) || y >= chars.GetLength(0) || visited[x, y])
yield break;
var nextstep = lastStep[chars[x, y]];
if (nextstep == null) // no word in this direction
yield break;
path.Push(new Point { X = x, Y = y });
if (nextstep.IsWord) // Victory! Found a word, return it...
yield return new BoggleSolution(nextstep.Word, path);
// Return possible longer words.
var newVisited = new bool[chars.GetLength(0), chars.GetLength(1)];
Array.Copy(visited, newVisited, visited.Length);
newVisited[x, y] = true;
foreach (var word in
FindWords(chars, newVisited, nextstep, path, x + 1, y).Concat(
FindWords(chars, newVisited, nextstep, path, x, y + 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x - 1, y)).Concat(
FindWords(chars, newVisited, nextstep, path, x, y - 1)))
yield return word;
path.Pop();
}
private static IEnumerable <BoggleSolution> FindWords(char[,] chars, bool[,] visited, CharDictionaryEntry lastStep, Stack <Point> path, int x, int y)
{
if (x < 0 || y < 0 || x >= chars.GetLength(0) || y >= chars.GetLength(0) || visited[x, y])
{
yield break;
}
var nextstep = lastStep[chars[x, y]];
if (nextstep == null) // no word in this direction
{
yield break;
}
path.Push(new Point {
X = x, Y = y
});
if (nextstep.IsWord) // Victory! Found a word, return it...
{
yield return(new BoggleSolution(nextstep.Word, path));
}
// Return possible longer words.
var newVisited = new bool[chars.GetLength(0), chars.GetLength(1)];
Array.Copy(visited, newVisited, visited.Length);
newVisited[x, y] = true;
foreach (var word in
FindWords(chars, newVisited, nextstep, path, x + 1, y).Concat(
FindWords(chars, newVisited, nextstep, path, x, y + 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x - 1, y)).Concat(
FindWords(chars, newVisited, nextstep, path, x, y - 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x + 1, y + 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x - 1, y - 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x - 1, y + 1)).Concat(
FindWords(chars, newVisited, nextstep, path, x + 1, y - 1)))
{
yield return(word);
}
path.Pop();
}
