def extendDownBeta(board, colIdx, rack, partialWord, currentNode, square, legalWords):
#Case 1: At the board's edge. Play currentNode and check validity of partialWord.
if(square == 14):
if '{' in currentNode.children:
rowIdx = square - len(partialWord) + 1
legalWords.append((partialWord, (colIdx, rowIdx), False ))
#Case 2: Still looking to place more tiles on the board after this move if we can
else:
#Case 2.1: If square next to where we want to place letter on currentNode on is empty.
if(board[square+1][colIdx].getChar() == '_'):
#Play and check if partial word is legal.
if '{' in currentNode.children:
rowIdx = square - len(partialWord) + 1
legalWords.append((partialWord, (colIdx, rowIdx), False ))
#Find a candidate tile to play at the next square and call extendRight on it
for child in currentNode.children:
if child in rack:
if board[square+1][colIdx].downCrossCheck[ord(child)-ord('a')] == True: #and it can be legally placed on the next square.
rack.remove(child)
extendDownBeta(board, colIdx, rack,partialWord + child, currentNode.children[child], square + 1, legalWords)
rack.append(child)
elif "*" in rack:
if board[square+1][colIdx].downCrossCheck[ord(child)-ord('a')] == True: #and it can be legally placed on the next square.
rack.remove("*")
extendDownBeta(board, colIdx, rack,partialWord + child, currentNode.children[child], square + 1, legalWords)
rack.append("*")
#Case 2.2: If square next to where we want to place letter from currentNode on is full. Hey, no worries!
#Just check if playing the occupying letter after currentNode will give us some valid prefix
else:
if board[square+1][colIdx].getChar() in currentNode.children:
extendDownBeta(board, colIdx, rack, partialWord + board[square+1][colIdx].getChar(), currentNode.children[board[square+1][colIdx].getChar()], square + 1, legalWords)
def upperPart(board, colIdx, rack, partialWord, currentNode, anchorSquare, limit, legalWords):
if anchorSquare > 0:
#Case 1: Above of anchor square occupied
if(board[anchorSquare-1][colIdx].getChar() != '_'):
upSquare = anchorSquare-1
upBit = board[upSquare][colIdx].getChar()
#Construct the existing upPart
while(upSquare > 0):
if(board[upSquare-1][colIdx].getChar() == '_'):
break
upSquare = upSquare - 1
upBit = board[upSquare][colIdx].getChar() + upBit
#Walk down the trie to node with upBit path. If it exists.
for element in upBit:
if element in currentNode.children:
currentNode = currentNode.children[element]
else:
return
#For each tile playable on anchorSquare
for child in currentNode.children:
if child in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendDownBeta(board, colIdx, rack, upBit + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendDownBeta(board, colIdx, rack, upBit + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")
#Case 2: Above of anchor square vacant
else:
#Check if partialWord formed so far can be placed above
pStart = anchorSquare - len(partialWord)
for i, letter in enumerate(partialWord):
if board[pStart+i][colIdx].downCrossCheck[ord(letter)-ord('a')] == False:
return
#print partialWord, limit, "survived!"
#For each tile playable on anchorSquare
for child in currentNode.children:
if child in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendDownBeta(board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendDownBeta(board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")
if limit > 0:
for child in currentNode.children:
if child in rack:
rack.remove(child)
upperPart( board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, limit-1, legalWords)
rack.append(child)
elif "*" in rack:
rack.remove("*")
upperPart( board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, limit-1, legalWords)
rack.append("*")
else:
for child in currentNode.children:
if child in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendDownBeta(board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[anchorSquare][colIdx].downCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendDownBeta(board, colIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")
def leftPart(board, rowIdx, rack, partialWord, currentNode, anchorSquare, limit, legalWords):
if anchorSquare > 0:
#Case 1: Left of anchor square occupied
if(board[rowIdx][anchorSquare-1].getChar() != '_'):
leftSquare = anchorSquare-1
leftBit = board[rowIdx][leftSquare].getChar()
#Construct the existing leftPart
while(leftSquare > 0):
if(board[rowIdx][leftSquare-1].getChar() == '_'):
break
leftSquare = leftSquare - 1
leftBit = board[rowIdx][leftSquare].getChar() + leftBit
#Walk down the trie to node with leftBit path
for element in leftBit:
if element in currentNode.children:
currentNode = currentNode.children[element]
else:
return #if it is not in trie then quit.
#For each tile playable on anchorSquare
for child in currentNode.children:
if child in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendRightBeta(board, rowIdx, rack, leftBit + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendRightBeta(board, rowIdx, rack, leftBit + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")
#Case 2: Left of anchor square vacant
else:
#Check if partial word formed so far can be placed to the left.
pStart = anchorSquare - len(partialWord)
for i, letter in enumerate(partialWord):
if board[rowIdx][pStart+i].acrossCrossCheck[ord(letter)-ord('a')] == False:
return
#print partialWord, limit, "survived!"
#For each tile playable on anchorSquare
for child in currentNode.children:
if child in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendRightBeta(board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendRightBeta(board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")
#If we can create even more leftParts
if limit > 0:
for child in currentNode.children:
if child in rack:
rack.remove(child)
leftPart( board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, limit-1, legalWords)
rack.append(child)
elif "*" in rack:
rack.remove("*")
leftPart( board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, limit-1, legalWords)
rack.append("*")
#Case 3: Nothing to the left of anchor square.
else:
for child in currentNode.children:
if child in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove(child)
extendRightBeta(board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append(child)
elif "*" in rack:
if board[rowIdx][anchorSquare].acrossCrossCheck[ord(child)-ord('a')] == True:
rack.remove("*")
extendRightBeta(board, rowIdx, rack, partialWord + child, currentNode.children[child], anchorSquare, legalWords)
rack.append("*")