源程序：
#include <iostream>
using namespace std;
template <typename T>
T abs(T x)
{
return x<0 ? -x : x;
}
int main()
{
int n = -5;
int m = 10;
double d = -.5;
float f = 3.2;
cout << n << "的绝对值是" << abs(n) << endl;
cout << m << "的绝对值是" << abs(m) << endl;
cout << d << "的绝对值是" << abs(d) << endl;
cout << f << "的绝对值是" << abs(f) << endl;
system("pause");
return 0;
}
运行结果：
