项目35-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; 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: transparent;"><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; 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; background-color: rgb(238, 238, 238);"><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; 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; background-color: rgb(238, 238, 238);"><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; 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: transparent;"><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; 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; background-color: rgb(238, 238, 238);"><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; 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; background-color: rgb(238, 238, 238);"><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; 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: transparent;"><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; 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; background-color: rgb(238, 238, 238);"><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; 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; background-color: rgb(238, 238, 238);"><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; 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: transparent;"><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; 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; background-color: rgb(238, 238, 238);"><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; 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; background-color: rgb(238, 238, 238);"><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

代码：

#include <iostream>
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);

//输入输出运算的重载
friend istream &operator>>(istream &in,CTime &t);
friend ostream &operator<<(ostream &out,CTime t);
//比较运算符(二目)的重载
bool operator > (CTime &t);
bool operator < (CTime &t);
bool operator >= (CTime &t);
bool operator <= (CTime &t);
bool operator == (CTime &t);
bool operator != (CTime &t);
//二目运算符的重载
CTime operator+(CTime &c);//返回c所规定的时、分、秒后的时间，例t1(8,20,25),t2(11,20,50)，t1+t2为:41:15
CTime operator-(CTime &c);//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
//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
//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
};
CTime::CTime(int h,int m,int s)
{
hour=h;
minute=m;
second=s;
}
void CTime::setTime(int h,int m,int s)
{
hour=h;
minute=m;
second=s;
}
istream &operator>>(istream &in,CTime &t)
{
char c1,c2;
while(1)
{
cin>>t.hour>>c1>>t.minute>>c2>>t.second;
if(c1==':'&&c2==':')
if(t.hour>=0&& t.hour<24 && t.minute>=0 && t.minute<60 && t.second>=0 && t.second<60)
break;
cout<<"输入的时间格式不正确"<<endl;
}
return in;
}
ostream &operator<<(ostream &out,CTime t)
{
out<<t.hour<<':'<<t.minute<<':'<<t.second;
return out;
}
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)//根据老师代码修改，使用this指针 区分
{
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)//>=和<一个意思
{
/*if (*this>=t)
return true;
*/
if (*this<t)
return false;
return true;
}
bool CTime::operator <= (CTime &t)
{
if (*this>t)
return false;
return true;
}
CTime CTime::operator + (CTime &t)
{

int h,m,s;
s=second+t.second;
m=minute+t.minute;
h=hour+t.hour;
if (s>59)
{
s-=60;
m++;
}
if (m>59)
{
m-=60;
h++;
}
while (h>23) h-=24;
CTime t0(h,m,s);
return t0;
}
CTime CTime::operator+(int s)
{
int ss=s%60;
int mm=(s/60)%60;
int hh=s/3600;
CTime t0(hh,mm,ss);
return *this+t0;
}
CTime CTime::operator - (CTime &t)
{
int h,m,s;
s=second-t.second;
m=minute-t.minute;
h=hour-t.hour;
if (s<0)
{
s+=60;
m--;
}
if (m<0)
{
m+=60;
h--;
}
while (h<0) h+=24;
CTime t0(h,m,s);
return t0;
}
CTime CTime::operator-(int s)
{
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)
{
CTime t=*this;
*this=*this+1;
return t;
}
CTime &CTime::operator++()
{
*this=*this+1;
return *this;
}
CTime CTime::operator--(int)
{
CTime t=*this;
*this=*this-1;
return t;
}
CTime &CTime::operator--()
{
*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)
{
*this=*this+s;
return *this;
}
CTime &CTime::operator-=(int s)
{
*this=*this-s;
return *this;
}

int main() //调用老师给出的测试函数
{
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：



学习心得：有2处错误怎么也找不出来，替换老师的就显示能正常运行，分别为程序的<重载和>重载，观察没发现有什么不正确。另外借鉴老师的this指针写法。