#include<stdlib.h>
#define QElemType int
#define OVERFLOW -2
#define OK 1
#define ERROR 0
#define MAXQSIZE 100
typedef struct{
QElemType *base;
int front;
int rear;
int length;
int maxsize;
}SqQueue;
int InitQueue(SqQueue &Q,int n)
{
Q.base=new QElemType[n];
if(Q.base==0)return 0;
Q.rear=Q.front=0;
Q.length=0;
Q.maxsize=n;
return 1;
}//構造空隊列Q
int QueueLength (SqQueue Q){
return (Q.rear -Q.front +MAXQSIZE) % MAXQSIZE;
}//返回Q的元素個數，即隊列的長度
int EnQueue(SqQueue &Q,QElemType e)
{
if(Q.length==Q.maxsize)return 0;
Q.base[Q.rear]=e;
Q.rear=(Q.rear++)%Q.maxsize ;
Q.length++;
return 1;
}//插入元素e為Q的新的隊尾元素
int DeQueue(SqQueue &Q,QElemType &e)
{
if(Q.length==0)return 0;
e=Q.base[Q.front];
Q.front=(Q.front+1)%Q.maxsize;
Q.length--;
return 1;
}//刪除Q的隊頭元素，用e返回其值
int GetHead(SqQueue Q,QElemType &e)
{
if(Q.length==0)return 0;
e=Q.base[Q.front];
return 1;
}
bool Empty(SqQueue Q)
{
if(Q.length==0)return true;
return false;
}
void print(SqQueue Q)
{
int k=Q.front;
for(int i=1;i<=Q.length;i++)
{
cout<<Q.base[k]<<" ";
k=(k+1)%Q.maxsize;
}
cout<<endl;
}
void main()
{
SqQueue Q;
QElemType e,i;
InitQueue(Q,10);
cout<<"1:輸入壹隊列"<<endl;
cout<<"2:隊列的刪除"<<endl;
cout<<"3:隊列的插入"<<endl;
cout<<"4:返回元素個數"<<endl;
cout<<"5:退出"<<endl;
int s;
cin>>s;
while(s!=5){
switch (s){
case 1:
cout<<"輸入6個元素組成隊列: ";
for(i=0;i<6;i++)
{
cin>>e;
EnQueue (Q,e);
}
print(Q);
break;
case 2:
if(Empty(Q))
cout<<"要刪除的元素不存在";
else
{
GetHead( Q,e);
cout<<"要刪除的元素為 :"<<e<<endl;
DeQueue(Q,e);
cout<<"元素刪除後的隊列為: ";
print(Q);
}
break;
case 3:
cout<<"輸入準備插入的元素: ";
cin>>e;
EnQueue(Q,e);
cout<<"插入後的隊列為： ";
print(Q); break;
case 4:
cout<<"元素個數為:";
cout<<QueueLength ( Q);
cout<<endl; break;
case 5:
cout<<"退出程序";
//return;
default: cout<<"輸入錯誤，請重新輸入!"<<endl;
}
cout<<endl<<"請繼續選擇:"<<endl;
cin>>s;
}
}