函数模板

 1 #include<iostream>
 2 using namespace std;
 3 template<typename T>//定义一个通用函数，T为类型参数
 4 
 5 
 6 T max(T a, T b, T c)//只能用在参数个数相同，参数类型不同
 7 {
 8     if (b > a)    a = b;
 9     if (c > a) a = c;
10     return a;
11 }
12 
13 int main()
14 {
15     int i1 = 185, i2 = -76, i3 = 567, i;
16     double d1 = 56.87, d2 = 90.23, d3 = -3214.78, d;
17     long l1 = 67854, l2 = -912456, l3 = 673456, l;
18 
19     i = max(i1, i2, i3);
20     d = max(d1, d2, d3);
21     l = max(l1, l2, l3);
22 
23     cout << "i_max=" << i << endl;
24     cout << "d_max=" << d << endl;
25     cout << "l_max=" << l << endl;
26     while (1);
27 }