booster.h

《数据结构、算法与应用》从C++语言应用角度列举了要点

#ifndef booster_
#define booster_

#include <iostream>

using namespace std;

struct booster
{
   int degradeToLeaf,           // degradation to leaf
       degradeFromParent;       // degradation from parent
   bool boosterHere;            // true iff booster here

   void output(ostream& out) const
   {out << boosterHere << ' ' << degradeToLeaf << ' '
        << degradeFromParent << ' ';}
};

// overload <<
ostream& operator<<(ostream& out, booster x)
   {x.output(out); return out;}
#endif