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# C++每日一题 Day 2 数字反转

***

lhy版权所有，禁止转载

### 知识点：输入输出，char类与string类

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### 本题提示：先尝试用自己能想到的方法做，如果还是不会则查看回答要求内的提示。

## 题目描述

输入一个不小于 100 且小于 1000，同时包括小数点后一位的一个浮点数，例如 123.4，要求把这个数字翻转过来，变成 4.321并输出。

## 输入

一行一个浮点数

## 输出

一行一个浮点数

## 输入输出样例

**输入**

```
123.4
```

**输出**

```
4.321
```

***

## 回答要求

* 附上你完成本程序的完整代码
* 你是否使用char类型来储存数据来做本题？如果不是，尝试一下（不一定要写出来）。

  思路：每个数字或`.`是否是一个字符？这五个数字（字符）一定要视为一个整体来处理吗？
* 什么是char类型？有什么用？能够储存什么？
* 拓展：c++中引入了新的一种类型字符串（string），尝试用String储存数据重新完成本题。（可能需要一些数组的知识，可以不做）


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