queen solution in python with yield
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
def queues(num = 8, state = ()):
for pos in range(num):
if not conflict(state, pos):
if len(state) == num - 1:
yield (pos,)
else:
for result in queues(num, state + (pos,)):
yield (pos,) + result