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#include <iostream>
#include <vector>
using namespace std;
template<typename T>
T max(T a,T b,T c)
{
cout<<"primary template"<<endl;
if(b>a)
{
a=b;
}
if(c>a)
{
a=c;
}
return a;
}
//形参个数不同的重载
template<typename T>
T max(T a, T b, T c, T d)
{
cout<<"override"<<endl;
if(b>a)
{
a=b;
}
if(c>a)
{
a=c;
}
return a;
}
//特化T max(T a,T b,T c)
#if 0 //ok
template<>
int max<int>(int a, int b, int c)
#else
//ok: explicit template argument int deduced fromparameter types
template<>
int max(int a, int b, int c)
#endif
{
cout<<"template specialization"<<endl;
if(b>a)
{
a=b;
}
if(c>a)
{
a=c;
}
return a;
}
//仅演示全特化/偏特化
template<typename T1>
bool min_test(T1 a, T1 b)
{
cout<<"min_test: primary template"<<endl;
return true;
}
#if 1
template<>
bool min_test<int>(int a, int b)
{
cout<<"min_test: full template specialization"<<endl;
return true;
}
#endif
//全特化:全部参数指定类型
//偏特化:部分参数指定类型
#if 0
//error: function template partial specialization ‘min_test<T1, int>’ is not allowed
template<typename T1, typename T2>
bool min_test<T1, int>(T1 a, int b)
{
cout<<"min_test: partial template specialization"<<endl;
return true;
}
#endif
typedef struct myval_s
{
int val0;
int val1;
}myval_t;
int main( )
{
int i1=185, i2=-76, i3=567, i;
double d1=56.87, d2=90.23, d3=-3214.78,d;
long g1=67854, g2=-912456, g3=673456, g;
i=max(i1,i2,i3);
cout<<"i_max="<<i<<endl<<endl;
d=max(d1,d2,d3);
cout<<"f_max="<<d<<endl<<endl;
g=max(g1,g2,g3);
cout<<"g_max="<<g<<endl<<endl;
g=max(g1,g2,g3,g3);
cout<<"g_max="<<g<<endl<<endl;
min_test(i1, i2);
min_test(d1, d2);
return 0;
}
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