from pythonds.graphs import Graph, Vertex
path = []
# posToNodeId将棋盘上的行列位置转换成与顶点编号相似的线性顶点数
def posToNodeId(row, column, board_size):
return (row * board_size) + column
# 判断走法是否合理
def legalCoord(x, bdsize):
if x >= 0 and x < bdsize:
return True
else:
return False
# genLegalMoves为辅助函数，创建一个列表，用于记录从这一格开始的所有合理走法。之后所有的合理走法都被转换成图中的边
def genLegalMoves(x, y, bdSize):
newMoves = [] # 创建一个列表
moveOffsets = [(-1, -2), (-1, 2), (-2, -1), (-2, -1), (1, -2), (1, 2), (2, -1), (2, 1)]
for tup in moveOffsets:
newX = x + tup[0]
newY = y + tup[1]
if legalCoord(newX, bdSize) and legalCoord(newY, bdSize):
newMoves.append((newX, newY))
return newMoves
# knightGraph 函数遍历整个棋盘
def knightGraph(bdSize):
ktGraph = Graph()
for row in range(bdSize):
for col in range(bdSize):
nodeId = posToNodeId(row, col, bdSize)
# 挑选出新的点
newPositions = genLegalMoves(row, col, bdSize)
for e in newPositions:
#
nid = posToNodeId(e[0], e[1], bdSize)
# 连接两点
ktGraph.addEdge(nodeId, nid)
return ktGraph
#
def knightTour(n, path, u, limit):
u.setColor('gray')
path.append(u)
# print("jin")
# print(u)
if n < limit:
nbrList = list(u.getConnections())
#print(len(nbrList))
i = 0
done = False
while i < len(nbrList) and not done:
#print(nbrList[i].getColor() == 'white')
if nbrList[i].getColor() == 'white':
done = knightTour(n + 1, path, nbrList[i], limit)
i = i + 1
if not done: # 准备回溯
path.pop()
u.setColor('white')
else:
done = True
return done
# 主函数
if __name__ == '__main__':
# 打印
g = knightGraph(5) # 创建所有点的有效路径的图
startVertex = g.getVertex(4)
knightTour(0, path, startVertex, 24)
for node in path:
print(node.getId(), end=' ')
# print(path)
