对于哲学家就餐问题,为了防止出现每位哲学家拿到一支筷子而出现死锁的情况,规定奇数号的哲学家必须首先拿左边的筷子,偶数号的哲学家则反之,请编写程序实现上述策略
时间: 2023-12-13 15:04:43 浏览: 87
好的,我可以帮你编写这个程序。这里我使用 Python 语言进行实现,你需要安装 Python 环境才能运行。
首先,我们需要定义一个哲学家类,包含哲学家编号、左右筷子编号、以及拿起和放下筷子的方法:
``` python
class Philosopher:
def __init__(self, idx, left_chopstick, right_chopstick):
self.idx = idx
self.left_chopstick = left_chopstick
self.right_chopstick = right_chopstick
def pick_left_chopstick(self):
return self.left_chopstick.acquire()
def pick_right_chopstick(self):
return self.right_chopstick.acquire()
def put_left_chopstick(self):
return self.left_chopstick.release()
def put_right_chopstick(self):
return self.right_chopstick.release()
```
接下来,我们创建哲学家和筷子的实例,以及定义哲学家就餐的方法:
``` python
import threading
n_philosophers = 5
chopsticks = [threading.Lock() for _ in range(n_philosophers)]
philosophers = [Philosopher(i, chopsticks[i], chopsticks[(i+1)%n_philosophers]) for i in range(n_philosophers)]
def dining_philosopher(philosopher):
while True:
if philosopher.idx % 2 == 0:
philosopher.pick_right_chopstick()
philosopher.pick_left_chopstick()
else:
philosopher.pick_left_chopstick()
philosopher.pick_right_chopstick()
# 哲学家进餐
print(f"Philosopher {philosopher.idx} is eating...")
philosopher.put_right_chopstick()
philosopher.put_left_chopstick()
# 哲学家思考
print(f"Philosopher {philosopher.idx} is thinking...")
```
最后,我们创建线程来运行程序:
``` python
threads = []
for philosopher in philosophers:
threads.append(threading.Thread(target=dining_philosopher, args=(philosopher,)))
for thread in threads:
thread.start()
for thread in threads:
thread.join()
```
这样,我们就实现了哲学家就餐的问题,避免了死锁的情况。
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