编辑代码

#include<stdio.h>
int main()
{
    int a;
    while(a!=0)
    {
        printf("menu-----\n");
        printf("sell-----1\n");
        printf("buy-----2\n");
        printf("show----3\n");
        printf("out-----0\n");
        scanf("%d",&a);
        switch(a)
        {
            case 1:
                printf("you are selling to consumer\n");
                break;
            case 2:
                printf("you are buying sometjing\n");
                break;
            case 3:
                printf("checking the store\n");
                break;
            case 0:
                printf("the program is out\n");
                break;
            default:
                printf("You put a wrong selection\n");
                break;    
        }
    }
    
    return 0;
}