泛型编程和函数指针

函数指针






#include<stdio.h>

int jug(int x, int y)

{

if (x >= 0)

return x;

else if (y == 0)

return x;

else

return x / y;

}

int sub(int x, int y)

{

return (x + y);

}

int minus(int x, int y)

{

return (x - y);

}

void test(int(*p)(int, int), int a, int b)

{

int Int1;

Int1 = (*p)(a, b);

printf("a=%d,b=%d\n", a, b, Int1);

}

int main()

{

int a = 1, b = 2, c = 3, d = 4, e = -5;

test(sub, a, b);

test(minus, c, d);

test(jug, e, b);

return 0;

}



#include<iostream>

using namespace std;

template<class T>

//建立一个静态模板库

class Operate{

public:

static T Add(T a, T b)

{

return a + b;

}

static T Mul(T a, T b)

{

return a - b;

}

static T Judge(T a, T b = 1)

{

if (a >= 0)

{

return a;

}

else

{

return a / b;

}

}

};

int main()

{

int A, B, C, D, E, x, y, z;

A = 1, B = 2, C = 3, D = 4, E = 5;

x = Operate<int>::Add(A, B);

y = Operate<int>::Mul(C, D);

z = Operate<int>::Judge(E, B);

cout << x << '\n' << y << '\n' << z << endl;

return 0;

}