functor returning 0
c++, stl
Solution
`for_each` takes the function by-value. That is, it uses a copy of the functor and not the functor itself. Your local `c` is left unchanged.
`for_each` returns the functor it used, though, so you could do:
Count c;
c = for_each(s.begin(), s.end(), c);
Or more idiomatically:
Count c = for_each(s.begin(), s.end(), Count());
However, there exists such functionality already (no need for your functor):
int total = std::accumulate(s.begin(), s.end(), 0);
Problem
I've recently started teaching myself the standard template library. I was curious as to why the GetTotal() method in this class is returning 0? ``` ... class Count { public: Count() : total(0){} void operator() (int val){ total += val;} int GetTotal() { return total;} private: int total; }; void main() { set<int> s; Count c; for(int i = 0; i < 10; i++) s.insert(i); for_each(s.begin(), s.end(), c); cout << c.GetTotal() << endl; } ```