Question

我是c ++初学者，我想编写一个USD / EUR交换程序，对于输出，我想写：“您得到多少美元/欧分，但是我不知道如何，因为我有只输出美分。

double eur{0},usd{0},sum{0},kurs{1.14},x,c,d,y;

cout<<"Do you want change Euro or Dollar?"<<endl<<"a is for Euro in Dollar, b is for Dollar in Euro, put a oder b in: "<<endl;

char input = ' ';
cin>>input;
cout<<"Give the sum you want to exchange: ";
cin>>sum;
if (input == 'a'){
    usd=sum;
    x=usd*kurs;
    y= x*100%100; (MODULO is not usable, error, why?)

    cout<<"You get "<< x <<" dollar and " << y << "cents."

Answer 1

您可以使用floor函数获取整数部分并将其从您的数字中减去。

Item.first.user.image_url(:original)

  Item Load (1.5ms)  SELECT  `items`.* FROM `items` ORDER BY `items`.`id` ASC LIMIT 1
  User Load (0.7ms)  SELECT  `users`.* FROM `users` WHERE `users`.`id` = 1 LIMIT 1
=> "https://xx.s3.ap-northeast-1.amazonaws.com/store/user/1/image/original-xx”

Item.first.user.id
   (19.0ms)  SET NAMES utf8mb4,  @@SESSION.sql_mode = CONCAT(CONCAT(@@sql_mode, ',STRICT_ALL_TABLES'), ',NO_AUTO_VALUE_ON_ZERO'),  @@SESSION.sql_auto_is_null = 0, @@SESSION.wait_timeout = 2147483
  Item Load (0.9ms)  SELECT  `items`.* FROM `items` ORDER BY `items`.`id` ASC LIMIT 1
  User Load (0.8ms)  SELECT  `users`.* FROM `users` WHERE `users`.`id` = 1 LIMIT 1
=> 1

如何只输出点号，并在点前切出整数？

1 个答案: