循环队列

****循环链表是为了避免假溢出现象***

#include <stdio.h>

#include <stdlib.h>
#define MAXSIZE 20


typedef int datatype;
typedef struct {
datatype data[MAXSIZE];
int rear,front;
}SeQueue;
  
SeQueue* InitSeQueue(); //队列初始化
void InSeQueue(); //入队操作
void OutSeQueue(); //出队操作
void FrontSeQueue(); //读队头元素
void EmptySeQueue(); //判队空操作


void main () {
SeQueue *sq;
datatype x1 = 10;
datatype x2;
sq = (SeQueue*)malloc(sizeof(SeQueue));
sq = InitSeQueue();
InSeQueue(sq,x1);
printf("%d\n",sq->data[9]);
EmptySeQueue(sq);
FrontSeQueue(sq);
OutSeQueue(sq,x2);
FrontSeQueue(sq);
}


//指空队
SeQueue* InitSeQueue () {
SeQueue *q;
q = (SeQueue*)malloc(sizeof(SeQueue));
q->front = 6;
q->rear = 8;
q->data[6] = 7;
q->data[7] = 8;
q->data[8] = 9;
return q;
}


//入队
void InSeQueue (SeQueue *q, datatype x) {
if ((q->rear+1) % MAXSIZE == q->front) {
printf("队满");
}
else {
q->rear = (q->rear+1) % MAXSIZE;
q->data[q->rear] = x;
}
}


//出队 
void OutSeQueue (SeQueue *q, datatype *x) {
if (q->front == q->rear) {
printf("队空\n");
}
else {
q->front = (q->front+1) % MAXSIZE;
x = q->data[q->front];
}
}


//判队空
void EmptySeQueue (SeQueue *q) {
if (q->front == q->rear)
printf("队空\n");
else
printf("不队空\n");
}
//读队头元素
void FrontSeQueue(SeQueue *q) {
printf("头元素 = %d\n",q->data[q->front]);

}

****循环链表是为了避免假溢出现象***