1226.py

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sample 48 ms submission
from threading import Lock

class DiningPhilosophers:
    
    forks = [Lock() for _ in range(5)]
    even = Lock()
    
    # call the functions directly to execute, for example, eat()
    def wantsToEat(self,
                   philosopher: int,
                   pickLeftFork: 'Callable[[], None]',
                   pickRightFork: 'Callable[[], None]',
                   eat: 'Callable[[], None]',
                   putLeftFork: 'Callable[[], None]',
                   putRightFork: 'Callable[[], None]') -> None:
        
        i = philosopher
        if i % 2 == 0:
            self.even.acquire()
            
        right_fork = i
        left_fork = (i+1) % 5
        
        self.forks[right_fork].acquire()
        self.forks[left_fork].acquire()
        pickRightFork()
        pickLeftFork()
        eat()
        putLeftFork()
        putRightFork()
        self.forks[right_fork].release()
        self.forks[left_fork].release()
        if i % 2 == 0:
            self.even.release()
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sample 52 ms submission
import threading


class DiningPhilosophers:
    
    def __init__(self):
        self.lock = threading.Lock()

    # call the functions directly to execute, for example, eat()
    def wantsToEat(self,
                   philosopher: int,
                   pickLeftFork: 'Callable[[], None]',
                   pickRightFork: 'Callable[[], None]',
                   eat: 'Callable[[], None]',
                   putLeftFork: 'Callable[[], None]',
                   putRightFork: 'Callable[[], None]') -> None:
        with self.lock:
            pickLeftFork()
            pickRightFork()
            eat()
            putLeftFork()
            putRightFork()
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