int choice,i;
 double price;
 for(i=1;i<=5;i++){
  //以下5行显示菜单
  printf("[1]Select crisps\n"); //查询薯片价格
  printf("[2]Select popcorn\n"); //查询爆米花价格
  printf("[3]Select chocolate\n"); //查询巧克力价格
  printf("[4]Select cola\n"); //查询可乐价格
  printf("[0]exit\n"); //退出查询
  printf("Enter choice:");
  scanf("%d",&choice); 
  
  if(choice == 0) //如果输入为0，则提前结束循环 
   break; 
   
  switch(choice){
   case 1:price = 3.0;break;
   case 2:price = 2.5;break;
   case 3:price = 4.0;break;
   case 4:price = 3.0;break;
   default:price = 0.0;break;
  }
  
 printf("price = %0.1f\n",price);
 }
 printf("Thank you\n");
 return 0;