源程序：
#include<iostream>
#include<string>
using namespace std;
template<class T1, class T2>
class Pair
{
public:
T1 first;
T2 second;
Pair(T1 k, T2 v) :first(k), second(v) {}
bool operator<(const Pair<T1, T2>&p)const;
};
template<class T1,class T2>
bool Pair<T1, T2>::operator<(const Pair<T1, T2>&p)const
{
return first<p.first;
}
int main()
{
Pair<string, int>student1("Tom", 19);
Pair<string, int>student2("Jim", 21);
Pair<int, int>coordinate(10, 20);
Pair<string, string>dic("word", "单词");
cout << "学生:" << student1.first << "" << student1.second << endl;
cout << "学生:" << student2.first << "" << student2.second << endl;
cout << "坐标:" << coordinate.first << "" << coordinate.second << endl;
cout << "字典顶:" << dic.first << "" << dic.second << endl;
bool a = student1<student2;
if (a == 0) cout << student1.first << "位于" << student2.first << "之后" << endl;
else cout << student1.first << "位于" << student2.first << "之前" << endl;
system("pause");
return 0;
}
运行结果：
