void add()      /*增加模块*/
{
         int sum,i;
         int flag=0;
         char choice;
         system("cls");
         printf("\n\n **************** 添加车辆信息*******************\n");
       do
       { cars[i].num=++sum;
         printf("\n                车辆名称:");
         scanf("%s",cars[i].name);
         printf("\n                车辆类型:");   
         scanf("%s",cars[i].type);
         printf("\n                车辆颜色:");   
         scanf("%s",cars[i].colour);
         printf("\n                车辆数量 :");
         scanf("%s",cars[i].count);   
         printf("\n                车辆价格:");
          scanf("%s",cars[i].price);
         printf("\n                车辆备注:");
         scanf("%s",cars[i].beizhu);
           printf("\n                要继续吗？(Y/N)");
         choice=getch();
          if (choice=='y'||choice=='Y')
          {    printf("\n                继续!\n");
               i++;
              flag=1;
          }
         else flag=0;
       }while(flag==1);N=i+1;    (error C2106: '=' : left operand must be l-value)
    printf("please press any key to menu:");
        getch();  
        return ;
}

抄别人的，还改了下？
是不是？
我猜N是宏定义的常变量，原来应该是：
while(flag==1||N==i+1);