#include<iostream>

namespace foo
{
    int doSomething(int x, int y)
    {
        return x+y;
    }
}

namespace goo
{
    int doSomething(int x, int y)
    {
        return x-y;
    }
}

int main()
{
    std::cout << foo::doSomething(4,3) << "\n";
    std::cout << goo::doSomething(4,3) << "\n";
    return 0;
}