数据结构与算法（五）循环队列实现

• 接口

#ifndef __QUEUE_H__ 
#define __QUEUE_H__ 
#include <stdlib.h> 
#include <stdio.h> 
#include <stdbool.h> 
typedef int ElementType; 
#define MAXSIZE 5 
typedef struct QNode { 
   ElementType Data[MAXSIZE]; 
   int rear; 
   int front; 
   int count; 
}QNode; 
typedef QNode* Queue; 
Queue CreatQueue();// 
bool IsFull(Queue Q);// 
bool isEmpty(Queue Q);// 
void AddQ(Queue Q, ElementType item);// 
ElementType DeleteQ(Queue Q);// 
void Display(Queue Q); 

• 函数实现

#include "Queue.h" 
Queue CreatQueue() 
{ 
   Queue temp = (Queue)malloc(sizeof(QNode)); 
   temp->front = 0; 
   temp->rear = 0; 
   temp->count = 0; 
   return temp; 
} 
bool IsFull(Queue Q) 
{ 
   return (Q->count == MAXSIZE); 
} 
bool IsEmpty(Queue Q) 
{ 
   return (Q->count == 0); 
} 
void AddQ(Queue Q, ElementType item) 
{ 
   if(IsFull(Q)){ 
       printf("queue is full.\n"); 
       return; 
   } 
   Q->Data[Q->rear] = item; 
   Q->rear = (Q->rear + 1) % MAXSIZE; 
   Q->count++; 
} 
ElementType DeleteQ(Queue Q) 
{ 
   if (IsEmpty(Q)) { 
       printf("queue is empty.\n"); 
       return 0; 
   } 
   ElementType firstData = Q->Data[Q->front]; 
   Q->front = (Q->front + 1) % MAXSIZE; 
   Q->count--; 
   return firstData; 
} 
void Display(Queue Q) 
{ 
   while (!IsEmpty(Q)) 
   { 
       printf("%d ", DeleteQ(Q)); 
   } 
   printf("\n"); 
}

• 测试函数

int main(int argc, char**argv) 
{ 
   Queue myQueue = CreatQueue(); 
   for (int i = 0; i < 10; i++) { 
       AddQ(myQueue, i); 
   } 
   Display(myQueue); 
   for (int i = 100; i < 105; i++) { 
       AddQ(myQueue, i); 
   } 
   Display(myQueue); 
   return 0; 
}

• 测试结果

• GitHub地址：

https://github.com/baiyu2017/baiyu2021.git