题解 | #【模板】循环队列#

#include<stdio.h>
#include<string.h>
#define true 1
#define false 0;
typedef int _bool;

 int main(void){
    int x = 0;//代表可利用空间大小
    int data_Num = 0;//表示队列内元素个数
    scanf("%d",&x);//输入可利用空间大小
    int data[x];
    int front = 0;//队头元素
    int rear = 0;//元素将添加的位置的下标
    int n = 0;//操作次数
    char str[6];//存储操作名
    scanf("%d",&n);//输入操作次数
    int num = 0;
    while (n > 0) {

        scanf("%s",str);//输入命令
        //解析操作命令
        if(strcmp(str,"push") == 0){
            scanf("%d",&num);//输入入队的数据
            if(data_Num >= x){
                //已满
                printf("full\n");
            } 
            else{
            data[rear] = num;
            rear = (rear + 1) % x;
            data_Num++;
            }

        }
        else if(strcmp(str,"front") == 0){
            if(data_Num == 0){
                //空
                printf("empty\n");
            }else{
                printf("%d\n",data[front]);
            }
        }
        else if(strcmp(str,"pop") == 0){
                 if(data_Num == 0){
                //空
                printf("empty\n");
            }else{
                printf("%d\n",data[front]);
                front = (front + 1) % x;
                if(data_Num > 0){
                data_Num--;}
            }
        }
        for(int i = 0; i < 6;i++){
            str[i] = ' ';
           }
        n--;
        }
        return 0;
    }