数据结构.队列的链式实现&&双端队列

一、初始化

#include
using namespace std;
typedef struct LinkNode {
    int data;
    LinkNode* next;
}LinkNode;
typedef struct {
    LinkNode* front, * rear;
}LinkQueue;
void Init(LinkQueue& Q)//带头结点初始化
{
    Q.front = Q.rear = (LinkNode*)malloc(sizeof(LinkNode));
    Q.front->next = NULL;
}
void Init(LinkQueue& Q)//不带头结点初始化
{
    Q.front = NULL;
    Q.rear = NULL;
}

二、判断是否为空

bool Empty(LinkQueue& Q)//带头结点判断为空
{
    if (Q.front == Q.rear)return true;
    else return false;
}
bool Empty(LinkQueue& Q)//不带头结点判断为空
{
    if (Q.front ==NULL)return true;
    else return false;
}

三、入队

void Push(LinkQueue& Q,int x)//带头结点入队
{
    LinkNode* s = (LinkNode*)malloc(sizeof(LinkNode));
    s->data = x;
    s->next = NULL;
    Q.rear->next = s;
    Q.rear = s;
}
void Push(LinkQueue& Q, int x)//不带头结点入队
{
    LinkNode* s = (LinkNode*)malloc(sizeof(LinkNode));
    s->data = x;
    s->next = NULL;
    if (Q.front == NULL)
    {
        Q.front = s;
        Q.rear = s;
    }
    else {
        Q.rear->next = s;
        Q.rear = s;
    }
}

四、出队

void Pop(LinkQueue& Q, int& x)//带头结点出队
{
    LinkNode* p = Q.front->next;
    x = p->data;
    Q.front->next = p->next;
    free(p);
}
void Pop(LinkQueue& Q, int& x)//不带头结点出队
{
    LinkNode* p = Q.front;
    x = p->data;
    Q.front = p->next;
    free(p);
}

五。双端队列