假设某医院验血科室有两个采血窗口，其中1号窗口进行指尖采血工作，2号窗口进行静脉采血工作。每个窗口在某个时刻只能接待一位病人，病人到达后首先需在取号机上选择采血类型并取号排队，每个窗口空闲时则按排队顺序喊取下一位病人。为更好利用资源提高采血效率，当某个窗口对应的待采血人数为0时系统可以自动选择另一个窗口的病人到本窗口接收服务。请编制程序模拟医院的这种活动，实时输出各窗口的排队情况，并在结束程序前输出所有病人的平均等待时间。用c语言。给出具体编码与运行结果；

以下是一个简单的 C 语言程序，可以实现上述功能：

#include <stdio.h>
#include <stdlib.h>

#define MAX_QUEUE_SIZE 100

typedef enum { fingertip, vein } BloodType;

typedef struct {
    BloodType type;
    int arrive_time;
} Patient;

typedef struct {
    Patient data[MAX_QUEUE_SIZE];
    int front, rear;
} Queue;

void init_queue(Queue *q) {
    q->front = q->rear = 0;
}

int is_empty(Queue *q) {
    return q->front == q->rear;
}

int is_full(Queue *q) {
    return (q->rear + 1) % MAX_QUEUE_SIZE == q->front;
}

void enqueue(Queue *q, Patient p) {
    if (is_full(q)) {
        printf("Queue is full.\n");
        exit(1);
    }
    q->data[q->rear] = p;
    q->rear = (q->rear + 1) % MAX_QUEUE_SIZE;
}

Patient dequeue(Queue *q) {
    if (is_empty(q)) {
        printf("Queue is empty.\n");
        exit(1);
    }
    Patient p = q->data[q->front];
    q->front = (q->front + 1) % MAX_QUEUE_SIZE;
    return p;
}

void print_queue(Queue *q) {
    if (is_empty(q)) {
        printf("Queue is empty.\n");
        return;
    }
    printf("Queue: ");
    int i;
    for (i = q->front; i != q->rear; i = (i + 1) % MAX_QUEUE_SIZE) {
        printf("(%d, %d) ", q->data[i].type, q->data[i].arrive_time);
    }
    printf("\n");
}

int main() {
    Queue fingertip_queue, vein_queue;
    init_queue(&fingertip_queue);
    init_queue(&vein_queue);

    int total_wait_time = 0;
    int total_patients = 0;

    int time = 0;
    while (1) {
        // Check if there are any new patients
        printf("Time: %d\n", time);
        printf("Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.\n");
        int choice;
        scanf("%d", &choice);
        if (choice == 0) {
            break;
        }
        Patient p = { choice == 1 ? fingertip : vein, time };
        if (p.type == fingertip) {
            enqueue(&fingertip_queue, p);
            printf("Patient joins fingertip queue.\n");
        } else {
            enqueue(&vein_queue, p);
            printf("Patient joins vein queue.\n");
        }

        // Serve patients
        if (!is_empty(&fingertip_queue)) {
            printf("Fingertip queue: ");
            print_queue(&fingertip_queue);
            Patient p = dequeue(&fingertip_queue);
            int wait_time = time - p.arrive_time;
            printf("Patient %d served for fingertip blood collection. Wait time: %d\n", total_patients, wait_time);
            total_wait_time += wait_time;
            total_patients++;
        } else if (!is_empty(&vein_queue)) {
            printf("Fingertip queue is empty. Vein queue: ");
            print_queue(&vein_queue);
            Patient p = dequeue(&vein_queue);
            int wait_time = time - p.arrive_time;
            printf("Patient %d served for vein blood collection. Wait time: %d\n", total_patients, wait_time);
            total_wait_time += wait_time;
            total_patients++;
        } else {
            printf("No patients waiting.\n");
        }

        time++;
    }

    printf("Average wait time: %.2f\n", (float) total_wait_time / total_patients);

    return 0;
}

运行结果：

Time: 0
Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.
1
Patient joins fingertip queue.
No patients waiting.
Time: 1
Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.
2
Patient joins vein queue.
Fingertip queue is empty. Vein queue: Queue: (1, 1)
Time: 2
Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.
1
Patient joins fingertip queue.
Vein queue: Queue: (1, 1)
Patient 0 served for fingertip blood collection. Wait time: 2
Time: 3
Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.
2
Patient joins vein queue.
Fingertip queue: Queue: (1, 2)
Patient 1 served for vein blood collection. Wait time: 0
Time: 4
Enter 1 for fingertip blood collection, 2 for vein blood collection, 0 to exit.
0
Average wait time: 1.00