用c++写In the online judge system, a judge file may include multiple datasets to check whether the submitted program outputs a correct answer for each test case. This task is to practice solving a problem with multiple datasets. Write a program which reads an integer x and print it as is. Note that multiple datasets are given for this problem. 输入 The input consists of multiple datasets. Each dataset consists of an integer x in a line. The input ends with an integer 0. You program should not process (print) for this terminal symbol. 输出 For each dataset, print x in the following format: Case i: x where i is the case number which starts with 1. Put a single space between "Case" and i. Also, put a single space between ':' and x.

以下是用 C++ 编写的解题代码：

#include <iostream>

using namespace std;

int main() {
    int x, i = 1;
    while (cin >> x && x != 0) {
        cout << "Case " << i << ": " << x << endl;
        i++;
    }
    return 0;
}

这个程序使用了一个 while 循环来不断读入输入数据，直到读入的数据为 0 为止。在循环中，我们输出当前的 case 编号和输入的整数值。需要注意的是，每个 case 编号后面要输出一个冒号和一个空格。

在输出时，我们使用了 `endl` 来输出一个换行符。这样做可以确保每组数据的输出都占用一行，并且在输出结束后换行，方便阅读。