链式队列的实现

#include

using namespace std;

struct QueueNode{

int data;

QueueNode* next;

};

struct LinkQueue{

QueueNode* top;

QueueNode* rear;

};

void InitQueue(LinkQueue*& Q) {

Q = new LinkQueue;

Q->top = Q->rear = new QueueNode; //设头结点便于操作

Q->top->next = 0;

}

int Push(LinkQueue*& Q, int x) {

QueueNode* p = new QueueNode;

if (p == 0) return 0;

p->data = x;

p->next = 0;

Q->rear->next = p;

Q->rear = p;

return 1;

}

int Pop(LinkQueue*& Q) {

if (Q->rear == Q->top) return 0;

QueueNode* p = Q->top->next;

if (p->next == 0) {

Q->top->next = 0;

Q->rear = Q->top;

}

else {

Q->top->next = p->next;

}

delete p;

return 1;

}

int GetTop(LinkQueue* Q,int &x) { //得到队头元素

if (Q->rear == Q->top) return 0;

x = Q->top->next->data;

return 1;

}

bool IsEmpty(LinkQueue* Q) { //判断列表是否为空

if (Q->rear == Q->top)

return true;

return false;

}

void Print(LinkQueue* Q) { //打印队列

QueueNode* p = Q->top->next;

while (p){

if (p != Q->top->next) cout << ' ';

cout << p->data;

p = p->next;

}

cout << endl;

}

int main() {

LinkQueue* Q;

InitQueue(Q);

Push(Q, 1);

Push(Q, 2);

Push(Q, 3);

Push(Q, 4);

Push(Q, 5);

Print(Q);

cout << IsEmpty(Q) << endl;

int x;

GetTop(Q, x);

cout << x << endl;

Pop(Q);

Print(Q);

Pop(Q);

Pop(Q);

Pop(Q);

Pop(Q);

Pop(Q);

cout << IsEmpty(Q);

return 0;

}