semaphore_dining_philosopher.ipynb

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    "import threading\n",
    "import time\n",
    "import random\n",
    "\n",
    "NUM_PHILOSOPHERS = 5\n",
    "chopsticks = [threading.Semaphore(1) for _ in range(NUM_PHILOSOPHERS)]\n",
    "\n",
    "def philosopher(philosopher_id):\n",
    "    # Get the left and right chopsticks for the philosopher\n",
    "    left_chopstick = chopsticks[philosopher_id]\n",
    "    right_chopstick = chopsticks[(philosopher_id + 1) % NUM_PHILOSOPHERS]\n",
    "\n",
    "    while True:\n",
    "        # Thinking\n",
    "        print(f\"Philosopher {philosopher_id} is thinking.\")\n",
    "        time.sleep(random.random())\n",
    "\n",
    "        # Pick up left chopstick\n",
    "        left_chopstick.acquire()\n",
    "        print(f\"Philosopher {philosopher_id} picked up the left chopstick.\")\n",
    "\n",
    "        # Try to pick up right chopstick without blocking\n",
    "        if right_chopstick.acquire(blocking=False):\n",
    "            # Pick up right chopstick and start eating\n",
    "            print(f\"Philosopher {philosopher_id} picked up the right chopstick.\")\n",
    "            print(f\"Philosopher {philosopher_id} is eating.\")\n",
    "            time.sleep(random.random())\n",
    "\n",
    "            # Release right chopstick after eating\n",
    "            right_chopstick.release()\n",
    "            print(f\"Philosopher {philosopher_id} put down the right chopstick.\")\n",
    "        \n",
    "        # Release left chopstick after eating or if right chopstick is not available\n",
    "        left_chopstick.release()\n",
    "        print(f\"Philosopher {philosopher_id} put down the left chopstick.\")\n",
    "\n",
    "if __name__ == \"__main__\":\n",
    "    # Create philosopher threads and start them\n",
    "    philosophers = [threading.Thread(target=philosopher, args=(i,)) for i in range(NUM_PHILOSOPHERS)]\n",
    "    for p in philosophers:\n",
    "        p.start()\n",
    "\n",
    "    # Wait for all philosopher threads to complete\n",
    "    for p in philosophers:\n",
    "        p.join()\n"
   ]
  }
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