/*
purpose:
编制一个超市帐务管理程序。假设某超市试营业期间销售10种商品，
商品信息包括商品名称、8位条形码、批发价、零售价、库存等。要求实现如下功能：
编写主菜单。
模拟顾客购物结账过程，输出购物小票，并修改商品信息。
统计当天营业额。
按销量评出最畅销商品。
*/
#include"stdio.h"
#include"stdlib.h"
#include"string.h"
#include"conio.h"
#define N 10
void printmenu()
{
   int i=0;
      printf("\n\t欢迎使用YQ超市账务管理系统\n");
    for(;i<50;i++)
       printf("*");
    printf("\n1\t输入商品条形码\n");
    printf("2\t结账\n");
    printf("3\t当天营业额\n");
    printf("4\t最畅销商品\n");
    printf("5\t退出\n");
     for(i=0;i<50;i++)
       printf("*");
     printf("\n");
      
}
struct information{
    char name[N];//{"毛巾","牙膏","零食","衣服","饮料","书本","水果","纸巾","杯具","笔"};
    char no[N];//{"001","002","003","004","005","006","007","008","009","010"};
 int num;//库存
 int num2;//售出
 double pp;//批发价
 double sp;//售价
}goods[N]={"毛巾","000",200,0,1.5,1.9,
           "牙膏","001",200,0,5.0,5.7,
           "零食","002",500,0,1.4,2.0,
           "衣服","003",1000,0,60,79,0,
           "饮料","004",1000,0,1.2,1.8,
           "书本","005",1500,0,0.5,1,
           "水果","006",400,0,1.5,2.0,
           "纸巾","007",1000,0,1.2,1.8,
           "杯具","008",200,0,35,40,
           "笔","009",2000,0,1.0,1.5
};
double sum,sumt=0;
void inputcode()
{
    int n,i;char code[N];
    printf("请输入商品的条形码和数量,条形码为010时结束全部输入\n");
    printf("#############超 市 购 物 小 票##############\n");
    printf("代码\t数量\t商品\t价格\n");
    sum=0;
    do
    {
     
     scanf("%s%d",&code,&n);
     printf("\t");
     for(i=0;i<N;i++)
        if (strcmp(code,goods[i].name)==0)
            break;
     goods[i].num-=n;
     goods[i].num2+=n;
     sum+=(goods[i].sp)*n;
     printf("%s\t%lf\t%d\n",goods[i].name,(goods[i].sp)*n);
    }
    while(strcmp(code,"010")!=0);
    sumt+=sum;
}
void calculate()
{
 float shou;
 printf("收款:\t");
 scanf("%f",&shou);
 printf("\n找零:\t%lf\n",sum-shou);
 printf("######\t欢迎下次再来!\t######\n");
}

void best()
{
    int i,k;
    k=0;
    for (i=1;i<N;i++)
     if (goods[k].num2<goods[i].num2) k=i;
    printf("今日最畅销的商品是 代码%s\t名称%s\t单价%lf\t销售量%d\n",goods[k].no,goods[k].name,goods[k].sp,goods[k].num2);

}
void main()
{char ch;
 int i=0;
printmenu();
  
  for (;i==0;){
    ch=getch();//scanf("%c",&ch);
    switch(ch)
    {
        case '1':inputcode();break;
        case '2':calculate();break;
        case '3':printf("今日营业额为%lf￥\n",sumt);break;
        case '4':best();break;
        case '5':i=1;break;
        default:printf("请重新输入\n");break;
    }
    printf("\n");
}
}

按思路，输入代码和数量，回车，就会打出信息并在内部处理。
我有把inputcode函数里面printf的i不小心打成n的时候 能输出goods【n】的信息 但是改成i 就不行了 全是0
谢谢指教！！！