顺序循环队列的基本操作

#include
#include
#define OK 1
#define ERROR 0
typedef int Status; // Status是函数的类型,其值是函数结果状态代码,如OK等
typedef int QElemType;
#define MAXQSIZE 100 // 最大队列长度(对于循环队列,最大队列长度要减1)
 
typedef struct
{
    QElemType *base; // 初始化的动态分配存储空间
    int front; // 头指针,若队列不空,指向队列头元素
    int rear; // 尾指针,若队列不空,指向队列尾元素的下一个位置
} SqQueue;
 
//创建队列
Status InitQueue(SqQueue &Q)
{
// 构造一个空队列Q,该队列预定义大小为MAXQSIZE
    Q.base=(QElemType *)malloc(sizeof(SqQueue)*MAXQSIZE);
    if(Q.base==NULL)return ERROR;
    Q.front=Q.rear=0;
    return OK;
}
 
//入队
Status EnQueue(SqQueue &Q,QElemType e)
{
// 插入元素e为Q的新的队尾元素
    if((Q.rear+1)%MAXQSIZE==Q.front) return ERROR;    //队满则不插入
    Q.base[Q.rear]=e;
    Q.rear=(Q.rear+1)%MAXQSIZE;
    return OK;
 
}
 
//出队
Status DeQueue(SqQueue &Q, QElemType &e)
{
// 若队列不空, 则删除Q的队头元素, 用e返回其值, 并返回OK; 否则返回ERROR
    if(Q.front==Q.rear)return ERROR;
    e=Q.base[Q.front];
    Q.front=(Q.front+1)%MAXQSIZE;
    return OK;
}
 
//取对头元素
Status GetHead(SqQueue Q, QElemType &e)
{
// 若队列不空,则用e返回队头元素,并返回OK,否则返回ERROR
    if(Q.front==Q.rear)return OK;
    e=Q.base[Q.front];
    return OK;
}
 
//计算队列的元素个数
int QueueLength(SqQueue Q)
{
    return (Q.rear-Q.front+MAXQSIZE)%MAXQSIZE;
 
}
 
//判断队列是否为空
Status QueueTraverse(SqQueue Q)
{
// 若队列不空,则从队头到队尾依次输出各个队列元素,并返回OK;否则返回ERROR.
    int i;
    i=Q.front;
    if(i==Q.rear)printf("The Queue is Empty!");  //请填空
    else
    {
        printf("The Queue is: ");
        while(i!=Q.rear)     //请填空
        {
            printf("%d ",Q.base[i]);   //请填空
            i = (i+1)%MAXQSIZE;   //请填空
        }
    }
    printf(" ");
    return OK;
}
 
//主函数
int main()
{
    int a;
    SqQueue S;
    QElemType x, e;
    if(InitQueue(S))    // 判断顺序表是否创建成功,请填空
    {
        printf("A Queue Has Created. ");
    }
    while(1)
    {
        printf("1:Enter 2:Delete 3:Get the Front 4:Return the Length of the Queue 5:Load the Queue 0:Exit Please choose: ");
        scanf("%d",&a);
        switch(a)
        {
        case 1:
            scanf("%d", &x);
            if(!EnQueue(S,x)) printf("Enter Error! "); // 判断入队是否合法,请填空
            else printf("The Element %d is Successfully Entered! ", x);
            break;
        case 2:
            if(!DeQueue(S,e)) printf("Delete Error! "); // 判断出队是否合法,请填空
            else printf("The Element %d is Successfully Deleted! ", e);
            break;
        case 3:
            if(!GetHead(S,e))printf("Get Head Error! "); // 判断Get Head是否合法,请填空
            else printf("The Head of the Queue is %d! ", e);
            break;
        case 4:
            printf("The Length of the Queue is %d! ",QueueLength(S));  //请填空
            break;
        case 5:
            QueueTraverse(S); //请填空
            break;
        case 0:
            return 1;
        }
    }
}
原文地址:https://www.cnblogs.com/yujon/p/5467617.html