Function pointer array

#include <iostream>

using namespace std;

double sum(const double, const double);
double product(const double, const double);
double subtract(const double, const double);
double (*pFunc[])(const double, const double) { sum, product, subtract };


int main(int args, char** argv)
{
    double a = atol(argv[1]), b = atol(argv[2]);
    double result = pFunc[0](a, b);
    cout << fixed << "Sum=" << result << endl;
    result = pFunc[1](a, b);
    cout << "Product=" << fixed << result << endl;
    result = pFunc[2](a, b);
    cout << "Subtract=" << fixed << result << endl;
}

double subtract(const double a, const double b)
{
    return a - b;
}

double product(const double a, const double b)
{
    return a * b;
}

double sum(const double a, const double b)
{
    return a + b;
}