#include <iostream>

#include <assert.h>

template <class T>

struct point{

inline point():x(0),y(0) {}

inline point(T _x, T _y):x(_x),y(_y){}

T x, y;

};

struct PointAccumulator{

typedef point<float> FloatPoint;

typedef point<double> Point;

/* before

PointAccumulator(int i=-1): acc(0,0), n(0), visits(0){assert(i==-1);}

*/

/*after begin*/

PointAccumulator(): acc(0,0), n(0), visits(0){}

PointAccumulator(int i): acc(0,0), n(0), visits(0){assert(i==-1);}

/*after end*/

inline void update(bool value, const Point& p=Point(0,0));

inline Point mean() const {return Point(1./n*acc.x, 1./n*acc.y);}

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inline operator double() const { return visits?(double)n/(double)visits:-1; }

operator int() const { return visits; }

inline void add(const PointAccumulator& p) {/*acc=acc+p.acc;*/ n+=p.n; visits+=p.visits; }

static const PointAccumulator& Unknown();

static PointAccumulator* unknown_ptr;

FloatPoint acc;

int n, visits;

inline double entropy() const;

};

int main(int argc, char **argv)

{

PointAccumulator test;

test.acc.x = 10.101;

test.acc.y = 11.111;

test.n = 1.0;

test.visits = 2.0;

std::cout << (double)test << std::endl;

std::cout << (int)test << std::endl;

return 0;

}