fizz buzz without "if"

fizz_buzz.cxx

// task: https://en.wikipedia.org/wiki/Fizz_buzz
// compile: g++ -std=c++14 -Wall -Wpedantic -Werror fizz_buzz.cxx -o fizz_buzz

#include <iostream>
#include <string>
namespace
{
std::string solve(int num);
}
int main()
{
    for(int num = 1; num <= 100; ++num)
    {
        std::cout << solve(num) << std::endl;
    }
    return 0;
}

namespace
{

using functor = std::string(*)(int);

std::string number(int num)
{
    return std::to_string(num);
}

std::string fizz(int)
{
    return "Fizz";
}

std::string buzz(int)
{
    return "Buzz";
}
std::string fizz_buzz(int)
{
    return "FizzBuzz";
}

functor solvers[2][2] = {
    { &number, &buzz      },
    { &fizz  , &fizz_buzz }
};

std::string solve(int num)
{
    return (solvers[0 == num % 3][0 == num % 5])(num);
}
}