第十二周上机实践项目 项目2-Time类中的运算符重载

问题及代码：

【项目-Time类中的运算符重载】 
　　实现Time类中的运算符重载。

<code class="hljs cpp has-numbering" style="display: block; padding: 0px; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> CTime
{
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span>:
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">unsigned</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">short</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> hour;    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 时</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">unsigned</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">short</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> minute;  <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 分</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">unsigned</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">short</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> second;  <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 秒</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span>:
    CTime(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> h=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> m=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> setTime(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> h,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> m,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> display();
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//二目的比较运算符重载</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> > (CTime &t);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> < (CTime &t);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> >= (CTime &t);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> <= (CTime &t);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> == (CTime &t);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> != (CTime &t);

    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//二目的加减运算符的重载</span>
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回t规定的时、分、秒后的时间</span>
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//例t1(8,20,25),t2(11,20,50)，t1+t2为19:41:15</span>
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>+(CTime &t);
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>-(CTime &t);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//对照+理解</span>
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>+(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回s秒后的时间</span>
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>-(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回s秒前的时间</span>
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//二目赋值运算符的重载</span>
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>+=(CTime &c);
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>-=(CTime &c);
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>+=(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回s秒后的时间</span>
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>-=(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> s);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//返回s秒前的时间</span>
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//一目运算符的重载</span>
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>++(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span>);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//后置++，下一秒</span>
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>++();<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//前置++，下一秒</span>
    CTime <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>--( <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span>);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//后置--，前一秒</span>
    CTime &<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>--();<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//前置--，前一秒</span>
};</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li></ul>

提示1：并不是所有比较运算重载函数都很复杂

<code class="hljs cs has-numbering" style="display: block; padding: 0px; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//比较运算返回的是比较结果，是bool型的true或false</span>
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//可以直接使用已经重载了的运算实现新运算，例如果已经实现了 > ，则实现 <= 就可以很方便了……</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> CTime::<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> <= (CTime &t) <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// 判断时间t1<=t2</span>
{
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (*<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span> > t) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>;
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li></ul>

甚至可以如下面的代码般简练：

<code class="hljs cs has-numbering" style="display: block; padding: 0px; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">bool</span> CTime::<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span> <= (CTime &t){<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> !(*<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span> > t)}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li></ul>

提示2：并不是所有复合赋值运算重载函数都需要很复杂

<code class="hljs cs has-numbering" style="display: block; padding: 0px; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//可以直接使用已经重载了的加减运算实现</span>
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//这种赋值, 例如 t1+=20，直接改变当前对象的值，所以在运算完成后，将*this作为返回值</span>
CTime &CTime::<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">operator</span>+=(CTime &c)
{
    *<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>=*<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>+c;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> *<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>;
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li></ul>

提示3：请自行编制用于测试的main()函数，有些结果不必依赖display()函数，提倡用单步执行查看结果

/*
 Copyright(c)2016,烟台大学计算机与控制工程学院
  All rights reserced
 文件名称：test.cpp
 作    者：蔡汝佳
 完成日期：2016年6月4日
 版 本 号：v1.0
 问题描述：
 输入描述：
 程序输出：
*/
#include <iostream>
#include <string>
using namespace std;
class CTime
{
private:
    unsigned short int hour;    // 时
    unsigned short int minute;  // 分
    unsigned short int second;  // 秒
public:
    CTime(int h=0,int m=0,int s=0);
    void setTime(int h,int m,int s);
    void display();
    //重载输入输出运算符
    friend istream &operator>>(istream &in,CTime &t);
    friend ostream &operator<<(ostream &out,CTime t);
    //二目的比较运算符重载
    bool operator > (CTime &t);
    bool operator < (CTime &t);
    bool operator >= (CTime &t);
    bool operator <= (CTime &t);
    bool operator == (CTime &t);
    bool operator != (CTime &t);

    //二目的加减运算符的重载
    //返回t规定的时、分、秒后的时间
    //例t1(8,20,25),t2(11,20,50)，t1+t2为19:41:15
    CTime operator+(CTime &t);
    CTime operator-(CTime &t);//对照+理解
    CTime operator+(int s);//返回s秒后的时间
    CTime operator-(int s);//返回s秒前的时间
    //二目赋值运算符的重载
    CTime &operator+=(CTime &c);
    CTime &operator-=(CTime &c);
    CTime &operator+=(int s);//返回s秒后的时间
    CTime &operator-=(int s);//返回s秒前的时间
    //一目运算符的重载
    CTime operator++(int);//后置++，下一秒
    CTime &operator++();//前置++，下一秒
    CTime operator--( int);//后置--，前一秒
    CTime &operator--();//前置--，前一秒
};
//构造函数
CTime::CTime(int h,int m,int s)
{
        hour=h;
        minute=m;
        second=s;
}
//设置时间
void CTime::setTime(int h,int m,int s)
{
     hour=h;
        minute=m;
        second=s;
}
  //二目的比较运算符重载
bool CTime::operator > (CTime &t)
{
    if(hour>t.hour)return true;
    if(hour<t.hour)return false;
    if(minute>t.minute)return true;
    if(minute<t.minute)return false;
    if(second>t.second)return true;
    return false;
}
bool CTime::operator < (CTime &t)
{
    if (hour<t.hour) return true;
    if (hour>t.hour) return false;
    if (minute<t.minute) return true;
    if (minute>t.minute) return false;
    if (second<t.second) return true;
    return false;
}
bool CTime::operator == (CTime &t)
{
    if(*this<t||*this>t)return false;
    return true;
}
bool CTime::operator >= (CTime &t)
{
    if(*this<t)return false;
    return true;
}
 bool CTime::operator <= (CTime &t)
 {
     if(*this>t)return false;
    return true;
 }
 bool CTime::operator != (CTime &t)
 {
     if(*this==t)return false;
     return true;
 }
 //二目的加减运算符的重载
CTime CTime::operator+(CTime &t)
{
    int h,m,s;
    h=hour+t.hour;
    m=minute+t.minute;
    s=second+t.second;
    if(s>59)
    {
        s-=60;
        m++;
    }
    if(m>59)
    {
        m-=60;
        h++;
    }
    if(h>23)
        h-=24;
    CTime t0(h,m,s);
    return t0;
}
CTime CTime::operator-(CTime &t)//对照+理解
{
    int h,m,s;
    h=hour-t.hour;
    m=minute-t.minute;
    s=second-t.second;
    if(s<0)
    {
        s+=60;
        m--;
    }
    if(m<0)
    {
        m+=60;
        h--;
    }
    if(h<0)
        h+=24;
    CTime t0(h,m,s);
    return t0;
}
CTime CTime::operator+(int s)//返回s秒后的时间
{
    int ss=s%60;
    int mm=(s/60)%60;
    int hh=s/3600;
    CTime t0(hh,mm,ss);
    return *this+t0;
}
CTime CTime::operator-(int s)//返回s秒前的时间
{
    int ss=s%60;
    int mm=(s/60)%60;
    int hh=s/3600;
    CTime t0(hh,mm,ss);
    return *this-t0;
}
CTime CTime::operator++(int )//后置++，下一秒
{
    CTime t;
    t=*this;
    *this=*this+1;
    return t;
}
CTime &CTime::operator++()//前置++，下一秒
{
    *this=*this+1;
    return *this;
}
CTime CTime::operator--( int)//后置--，前一秒
{
    CTime t;
    t=*this;
    *this=*this-1;
    return t;
}
CTime &CTime::operator--()//前置--，前一秒
{
    *this=*this-1;
    return *this;
}
CTime &CTime::operator+=(CTime &c)
{
    *this=*this+c;
    return *this;
}
CTime &CTime::operator-=(CTime &c)
{
    *this=*this-c;
    return *this;
}
CTime &CTime::operator+=(int s)//返回s秒后的时间
{
    *this=*this+s;
    return *this;

}
CTime &CTime::operator-=(int s)//返回s秒前的时间
{
    *this=*this-s;
    return *this;
}

istream &operator>>(istream &in,CTime &t)
{
    char ch1,ch2;
    while(1)
    {
        cout<<"请输入时间（hh:mm:ss）"<<endl;
        cin>>t.hour>>ch1>>t.minute>>ch2>>t.second;
        if(ch1==':'&&ch2==':')
            if(t.hour>-1&&t.hour<24&&t.minute>1&&t.minute<60&&t.second>-1&&t.second<60) break;
        cerr<<"时间格式输入错误！"<<endl;

    }
    return cin;
}
ostream &operator<<(ostream &out,CTime t)
{
    cout<<t.hour<<":"<<t.minute<<":"<<t.second<<endl;
    return out;
}
int main()
{
    CTime t1,t2,t;

    cout<<"t1为：";
    cin>>t1;
    cout<<"t2为：";
    cin>>t2;
    cout<<"下面比较两个时间大小：\n";
    if (t1>t2) cout<<"t1>t2"<<endl;
    if (t1<t2) cout<<"t1<t2"<<endl;
    if (t1==t2) cout<<"t1＝t2"<<endl;
    if (t1!=t2) cout<<"t1≠t2"<<endl;
    if (t1>=t2) cout<<"t1≥t2"<<endl;
    if (t1<=t2) cout<<"t1≤t2"<<endl;
    cout<<endl;
    cout<<"t1= "<<t1<<endl;
    cout<<"t2= "<<t2<<endl;

    cout<<"t=t1++"<<endl;
    t=t1++;
    cout<<"t= "<<t<<"    t1= "<<t1<<endl;

    cout<<"t=++t1"<<endl;
    t=++t1;
    cout<<"t= "<<t<<"    t1= "<<t1<<endl;

    cout<<"t1+t2= "<<t1+t2<<endl;
    cout<<"t1-t2= "<<t1-t2<<endl;
    cout<<"t1+2000= "<<t1+2000<<endl;
    cout<<"t1-5000= "<<t1-5000<<endl;
    return 0;
}

运行结果：

知识点总结：

运算符重载 

学习心得：