Is this notation possible in C++?

Question:

Is this notation possible in C++? add(1)(2); I met this expression in codvars tasks, the task is that with such a record, the function must sum up all the arguments passed to it, i.e. in the case of such a record add(1)(2); the answer should be 3 if the entry is add(1)(2)(3); then, respectively, 6. As far as I know, there is no such way of passing arguments to a function in c++.

Answer:

You can make a simple class:

#include <iostream>

using std::cout;
using std::endl;

class add
{
public:
    add(int val): sum(val) {}
    add& operator()(int val)
    {
        sum += val;
        return *this;
    }
    operator int() const
    {
        return sum;
    }
private:
    int sum;
};

int main()
{
    cout << add(1) << endl;
    cout << add(1)(2) << endl;
    cout << 5 + add(0)(1)(2)(3)(4)(5) << endl;
    return 0;
}

Conclusion :

1
3
20