init-commit

internbootcamp/libs/wordladder/solving/word_distance_map.py

@@ -0,0 +1,36 @@
+from collections import deque
+from libs.wordladder.words.word import Word
+
+
+class WordDistanceMap(object):
+    def __init__(self, word: Word, maximum_ladder_length: int = None):
+        self.distances = {str(word): 1}
+        queue = deque()
+        queue.append(word)
+        max_distance = maximum_ladder_length if maximum_ladder_length is not None else 255
+        while len(queue) > 0:
+            next_word: Word = queue.popleft()
+            distance = self.distances.get(str(next_word))
+            if distance is None:
+                distance = 0
+            distance = distance + 1
+            if distance <= max_distance:
+                for linked_word in next_word.linked_words:
+                    if linked_word not in self:
+                        queue.append(linked_word)
+                        self.distances[str(linked_word)] = distance
+
+    def __len__(self):
+        return len(self.distances)
+
+    def __contains__(self, word: Word):
+        return str(word) in self.distances
+
+    def __getitem__(self, word: Word):
+        return self.distances.get(str(word))
+
+    def reachable(self, word: Word, maximum_ladder_length: int):
+        distance = self.distances.get(str(word))
+        if distance is None:
+            return False
+        return distance <= maximum_ladder_length