第十六周项目3-max带来的冲突

分析下面程序出现的编译错误，给出解决的方案。

<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-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">#include<iostream></span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">using</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">namespace</span> <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">std</span>;
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//定义函数模板</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">template</span><<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> T>
T max(T a, T b)
{
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> (a>b)?a:b;
}

<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> main()
{
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> x=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span>,y=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">6</span>;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">double</span> x1=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">9.123</span>,y1=<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">12.6543</span>;
    <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">cout</span><<<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"把T实例化为int:"</span><<max(x,y)<<endl;
    <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">cout</span><<<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"把T实例化为double:"</span><<max(x1,y1)<<endl;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>;
}</code>

原因：

自定义的max和数据库中原有的max起了冲突

解决办法：

在使用的函数前加上::来表示引用的自定义max函数

改正如下：

#include<iostream>
using namespace std;
//定义函数模板
template<class T>
T max(T a, T b)
{
    return (a>b)?a:b;
}
int main()
{
    int x=2,y=6;
    double x1=9.123,y1=12.6543;
    cout<<"把T实例化为int:"<<::max(x,y)<<endl;
    cout<<"把T实例化为double:"<<::max(x1,y1)<<endl;
    return 0;
}

图片：

心得：

关于引用···还是再看看吧，很容易混淆