隊列是一種先進先出的數據結構,分順序存儲結構和鏈式存儲結構兩種。順序存儲結構中廣泛使用的是循環隊列,也是隊列使用中最多的一種。下面將分別實現這兩種隊列的基本操作。
#include<iostream>
using namespace std;
const int MaxSize = 100;
class queue
{
public:
queue()
{
front = 0;
rear = 0;
}
int isEmpty();
int enqueue(int x);
int dequeue();
void printqueue();
int lengthqueue();
protected:
private:
int data[MaxSize];
int front;
int rear;
};
int queue::isEmpty()
{
if (front == rear)
{
return 1;
}
else
{
return 0;
}
}
int queue:: enqueue(int x)
{
if ((rear + 1) % MaxSize == front)
{
cout << "隊列滿" << endl;
return 0;
}
data[rear] = x;
rear = (rear + 1) % MaxSize;
return 1;
}
int queue::dequeue()
{
int x;
if (isEmpty())
{
cout << "隊列空" << endl;
//return 0;
}
else
{
x = data[front];
front = (front + 1) % MaxSize;
return x;
}
}
int queue::lengthqueue()
{
return ((rear - front + MaxSize) % MaxSize);
}
void queue::printqueue()
{
for (int i = front; i < front+lengthqueue(); i = (i + 1) % MaxSize)
{
cout << data[i] << endl;
}
}
#include<iostream>
using namespace std;
class Node
{
public:
Node(int x)
{
data = x;
next = NULL;
}
int data;
Node *next;
};
class queue
{
public:
queue()
{
front = NULL;
rear = NULL;
}
int isEmpty();
void enqueue(int x);
int dequeue();
int lengthqueue();
void printqueue();
private:
Node *front;
Node *rear;
int length = 0;
};
int queue::isEmpty()
{
if (front == NULL)
{
return 1;
}
else
{
return 0;
}
}
void queue::enqueue(int x)
{
Node *temp = new Node(x);
if (isEmpty() == 1)
{
front = rear = temp;
}
else
{
rear->next = temp;
rear = temp;
}
}
int queue::dequeue()
{
if (isEmpty() == 1)
{
cout << "隊列爲空" << endl;
return -1;
}
else
{
Node *temp = front;
front = front->next;
return temp->data;
}
}
void queue::printqueue()
{
Node *p = front;
while (p != NULL)
{
cout << p->data;
cout << " ";
p = p->next;
}
cout << endl;
}
int queue::lengthqueue()
{
Node *p=front;
while (p!=NULL)
{
length++;
p = p->next;
}
return length;
}