Boggle_Board

Author: Partho Biswas

algoexpert.io/python/Boggle_Board.py

@@ -0,0 +1,51 @@
+def boggleBoard(board, words):
+    trie = Trie()
+    for word in words:
+        trie.add(word)
+    finalWords = {}
+    visited = [[False for lettern in row] for row in board]
+    for i in range(len(board)):
+        for j in range(len(board[i])):
+            explore(i, j, board, trie.root, visited, finalWords)
+    return list(finalWords.keys())
+
+
+def explore(i, j, board, trie, visited, finalWords):
+    if visited[i][j] == True:
+        return
+    letter = board[i][j]
+    if letter not in trie:
+        return
+    visited[i][j] = True
+    trieNode = trie[letter]
+    if "*" in trieNode:
+        finalWords[trieNode["*"]] = True
+    neighbours = getNeighbours(i, j, board)
+    for neighbour in neighbours:
+        explore(neighbour[0], neighbour[1], board, trieNode, visited, finalWords)
+    visited[i][j] = False
+
+
+def getNeighbours(i, j, board):
+    neighbours = []
+    possibleDirections = [(-1, 0), (-1, 1), (0, 1), (1, 1), (1, 0), (1, -1), (0, -1), (-1, -1)]
+    for direction in possibleDirections:
+        di, dj = direction
+        newI, newJ = i + di, j + dj
+        if 0 <= newI < len(board) and 0 <= newJ < len(board[0]):
+            neighbours.append([newI, newJ])
+    return neighbours
+
+
+class Trie:
+    def __init__(self):
+        self.root = {}
+        self.endSymbol = "*"
+
+    def add(self, word):
+        current = self.root
+        for letter in word:
+            if letter not in current:
+                current[letter] = {}
+            current = current[letter]
+        current[self.endSymbol] = word