simulate

import heapq

class Event:
    def __init__(self, time, event_type):
        self.time = time
        self.event_type = event_type  # 'arrival' or 'departure'

    def __lt__(self, other):
        return self.time < other.time

def bank_simulation(arrival_rate, service_rate, num_customers):
    events = []
    heapq.heappush(events, Event(0, 'arrival'))
    current_time = 0
    customers_served = 0
    queue_length = 0

    while len(events) > 0 and customers_served < num_customers:
        event = heapq.heappop(events)
        current_time = event.time

        if event.event_type == 'arrival':
            queue_length += 1
            if queue_length == 1:
                # First customer in queue, schedule departure
                service_duration = random.expovariate(service_rate)
                heapq.heappush(events, Event(current_time + service_duration, 'departure'))
            # Schedule next arrival
            arrival_duration = random.expovariate(arrival_rate)
            heapq.heappush(events, Event(current_time + arrival_duration, 'arrival'))
        elif event.event_type == 'departure':
            queue_length -= 1
            customers_served += 1

    return current_time, customers_served, queue_length

# 参数设置
arrival_rate = 1.0  # 客户到达率（人/分钟）
service_rate = 1.5  # 服务率（人/分钟）
num_customers = 100  # 总客户数

# 运行模拟
end_time, served, final_queue = bank_simulation(arrival_rate, service_rate, num_customers)
print(f"模拟结束时间: {end_time:.2f} 分钟")
print(f"服务客户数: {served}")
print(f"最终排队人数: {final_queue}")