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序号：64874 发表者：Cxt_ann 发表日期：2003-12-13 20:23:50
<br>主题：大家帮忙看一下啊！！
<br>内容：哪里不对？？<BR>/* 题目:<BR> * 定义一个大整数类型,<BR> * 重载四个符号 + - * /,<BR> * 分别进行两个大整数的加减乘除运算,<BR> * 输入输出要用友元函数来定义 <BR> */<BR><BR>//bigint.h<BR><BR>#ifndef BIGINT_H_<BR>#define BIGINT_H_<BR><BR>#include &lt;iostream.h&gt;<BR>//using namespace std;<BR><BR>class Int<BR>{<BR>private:<BR>&nbsp;&nbsp;&nbsp;&nbsp;long num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;<BR>public:<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int ();<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int operator+ ( const Int &amp; t ) const;<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int operator- ( const Int &amp; t ) const;<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int operator* ( const Int &amp; t ) const;<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int operator/ ( const Int &amp; t ) const;<BR>&nbsp;&nbsp;&nbsp;&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;friend istream &amp; operator&gt;&gt; ( istream &amp; is, const Int &amp; t )<BR>&nbsp;&nbsp;&nbsp;&nbsp;{<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;is &gt;&gt; t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return is;<BR>&nbsp;&nbsp;&nbsp;&nbsp;}<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;friend ostream &amp; operator&lt;&lt; ( ostream &amp; os, const Int &amp; t )<BR>&nbsp;&nbsp;&nbsp;&nbsp;{<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;os &lt;&lt; t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return os;<BR>&nbsp;&nbsp;&nbsp;&nbsp;}<BR>};<BR><BR>#endif<BR><BR>//bigint.cpp<BR><BR>#include &#34;bigint.h&#34;<BR>#include &lt;iostream.h&gt;<BR><BR>Int :: Int ()<BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;num = 0;<BR>}<BR><BR>Int Int :: operator+ ( const Int &amp; t ) const <BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int temp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;temp.num = num + t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;return temp;<BR>}<BR><BR>Int Int :: operator- ( const Int &amp; t ) const<BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int temp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;temp.num = num - t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;return temp;<BR>}<BR><BR>Int Int :: operator* ( const Int &amp; t ) const<BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int temp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;temp.num = num * t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;return temp;<BR>}<BR><BR>Int Int :: operator/ ( const Int &amp; t ) const<BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int temp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;temp.num = num / t.num;<BR>&nbsp;&nbsp;&nbsp;&nbsp;return temp;<BR>}<BR><BR>//usebigint.cpp<BR><BR>#include &lt;iostream.h&gt;<BR>//using namespace std;<BR>#include &#34;bigint.h&#34;<BR><BR>int main()<BR>{<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int A;<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int B;<BR>&nbsp;&nbsp;&nbsp;&nbsp;Int temp;<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Please input number1: &#34;;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cin &gt;&gt; A;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Please input number2: &#34;;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cin &gt;&gt; B;<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;temp = A + B;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Number1 + Number2 = &#34; &lt;&lt; temp &lt;&lt; endl;<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;temp = A - B;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Number1 - Number2 = &#34; &lt;&lt; temp &lt;&lt; endl;<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;temp = A * B;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Number1 * Number2 = &#34; &lt;&lt; temp &lt;&lt; endl;<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;temp = A / B;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Number1 / Number2 = &#34; &lt;&lt; temp &lt;&lt; endl;<BR>&nbsp;&nbsp;&nbsp;&nbsp;cout &lt;&lt; &#34;Done!\n&#34;;<BR>&nbsp;&nbsp;&nbsp;&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;return 0;<BR>}
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<font color=red>答案被接受</font><br>回复者：红苹果 回复日期：2003-12-14 00:13:10
<br>内容：主要是两个友元函数有错：<BR>1. 友元函数应该是在类中说明、类外定义。<BR>2. operator&gt;&gt; ( ostream &amp; os, const Int &amp; t )的第二个参数不能是const的，它要用来接受数据。<BR>修改后的代码看附件：<BR><BR>2003-12-14 13:07:49