#include <cassert>
#include <functional>
#include <vector>
#include <algorithm>

struct Player
{
  Player(const int anyX, const int anyY) : x(anyX), y(anyY) {}
  int x,y;
  //And more...
};

//From http://www.richelbilderbeek.nl
template <class T>
struct SameXandY : public std::unary_function<T,bool>
{
  explicit SameXandY(const T& position) : mPosition(position) {}
  bool operator()(const T& position) const
  {
    return position.x == mPosition.x && position.y == mPosition.y;
  }

  private:
  const T mPosition;
};


int main()
{
  std::vector<Player> v;
  for (int i=0; i!=10; ++i) v.push_back(Player(i,i));

  assert( std::find_if(v.begin(), v.end(), SameXandY<Player>(Player(3,5))) == v.end());
  assert( std::find_if(v.begin(), v.end(), SameXandY<Player>(Player(5,5))) != v.end());
}