队列的应用——就诊模拟系统

#include <iostream.h> #include <stdlib.h> #define NULL 0 typedef struct qnode { long int data; //存放元素 struct qnode *next; //下一个节点指针 }QNode; typedef struct { QNode * front; //队首 QNode * rear; //队尾 }LiQueue; void menu(); void InitQueue(LiQueue *&q); long int enQueue(LiQueue *q); void deQueue(LiQueue *&q , long int &e); void chaxun(LiQueue *q); int main() { LiQueue *q; long int e = 0; int n; InitQueue(q); do { menu(); cout << "\n请输入选项（1 <= n <= 5): "; while(cin >> n ) { if(n >= 1 && n <= 5) break; else cout << "您输入不合法请重新输入："; } switch(n) { case 1: cout << "\n请输入病历号： "; e = enQueue(q); break; case 2: deQueue(q,e); cout <<e << "号病人已就诊！\n"; e = 0; break; case 3: chaxun(q); break; case 4: chaxun(q); break; case 5: cout <<"谢谢您的使用，再见！\n"; break; } }while(n != 5); return 0; } void menu() { cout << "\n-----**医院就诊系统**------\n\n" ; cout<<" (1)排队 "<<endl; cout<<" (2)就诊 "<<endl; cout<<" (3)查看排队 "<<endl; cout<<" (4)不再排队,余下依次就诊 "<<endl; cout<<" (5)下班，退出 "<<endl; } void InitQueue(LiQueue *&q) { q = (LiQueue *)malloc(sizeof(LiQueue)); q ->front = q->rear = NULL; } // 1、排队 long int enQueue(LiQueue *q) { QNode *p; long int e; cout << "\n请输入您的病历号："; cin >> e; p = (QNode *)malloc(sizeof(QNode)); p ->data = e; p ->next = NULL; if(q ->rear == NULL) q ->front = q ->rear = p; else { q ->rear ->next = p; q -> rear = p; } return e; } void deQueue(LiQueue *&q , long int &e) { QNode *t; if(q -> rear == NULL) { cout << "当前没有排队病人哦！\n"; return ; } t = q ->front; if(q -> front == q -> rear) q -> front = q -> rear = NULL; else q ->front = q -> front -> next; e = t ->data; free(t); return ; } void chaxun(LiQueue *q) { QNode * p; if(q -> rear == NULL) cout << "没有病人在排队！" ; else { p = q ->front; while(p != NULL) { cout << p ->data << "\n"; p = p ->next; } } }