首先我们写一个conflict函数来判断下一个皇后的位置是否和前面的皇后的放置位置产生冲突.
def conflict(state,nextX):
nextY = len(state)
for i in range(nextY):
if abs(state[i] - nextX) in (0, nextY - i):
return True
return False
利用递归生成器
def queens(num = 8, state=()):
for pos in range(8):
if not conflict(state, pos):
if len(state) == num - 1:
yield (pos,)
else:
for result in queens(num, state + (pos,)):
yield (pos,) + result
主程序
if __name__== '__main__':
result = list(queens(8))
print(result)
num = len(result)
print(num)
结果:
[(0, 4, 7, 5, 2, 6, 1, 3), (0, 5, 7, 2, 6, 3, 1, 4), (0, 6, 3, 5, 7, 1, 4, 2), (0, 6, 4, 7, 1, 3, 5, 2)...]
92
