/*
       +--------------------+
       | Point              |<---+
       +--------------------+    |
       | String letterCoord |    |
       | int numCoord       |    |
       +--------------------+    |
                                 |
                                 |
      +---------------------+    |
      | Road                |<-------------+
      +---------------------+    |         |
      | String name         |    |         |
      | Point endOne        |----+         |
      | Point endTwo        |----+         |
      | RoadList intersects |---------+    |
      +---------------------+         |    |
                                      |    |
            +----------+              |    | 
            | RoadList |<-------------+    |
            +----------+              |    |
            +----------+              |    |
                / \                   |    |
                ---                   |    |
                 |                    |    |
       -------------------            |    |
       |                 |            |    |
  +---------+    +---------------+    |    |
  | NoRoad  |    | LargerRL      |    |    |
  +---------+    +---------------+    |    |
  +---------+    | Road first    |--- | ---+
                 | RoadList rest |----+
                 +---------------+ 
*/

class Point { 
  String letterCoord;
  int numCoord;

  Point( String letterCoord, int numCoord ) {
    this.letterCoord = letterCoord;
    this.numCoord = numCoord;
  }
}

class Road {

   String name;
   Point endOne, endTwo;
   RoadList intersects;

   Road( String name, Point endOne, Point endTwo, RoadList intersects) {
     this.name = name;
     this.endOne = endOne;
     this.endTwo = endTwo;
     this.intersects = intersects;
   }

   //s55th.numReachable() == 0
   //ellis.numReachable() == 3
   //To calculate how many roads can be reached from this one
   int numReachable() {
      /// this.name ... this.endOne.PointMethod() ... this.endTwo.PointMethod() ... this.intersects.RoadListMethod() 
      return this.intersects.count();
   }

}

abstract class RoadList {
  abstract int count();
}

class NoRoad extends RoadList {
  //To count how many Roads are in the NoRoad
  int count() {
    return 0;
  }
}

class LargerRL extends RoadList {
  Road first;
  RoadList rest;

  LargerRL( Road first, RoadList rest ) {
    this.first = first;
    this.rest = rest;
  }

  //ellis.intersects.count() == 3
  //To count how many roads are in this LargerRL and all intersecting roads
  int count() {
    // ... this.first.RoadMethod() .. this.rest.RoadList() ...
    return 1 + this.first.numReachable() + this.rest.count();
  }
}

/*
Road hw66 = new Road( "hw66", new Point("A",1), new Point("E",1), new NoRoad());
Road s55th = new Road( "55th", new Point("A",1), new Point("E",1), new NoRoad());
Road s56th = new Road( "56th", new Point("A",2), new Point("E",2), new NoRoad());
Road s57th = new Road( "57th", new Point("A",3), new Point("E",3), new NoRoad());
Road ellis = new Road(" ellis", new Point("A",1), new Point("A",8), new LargerRL(s55th, new LargerRL(s56th, new LargerRL( s57th, new NoRoad()))));

*/

class Road2 {

   String name;
   Point endOne, endTwo;
   RoadList2 intersects;

   Road2( String name, Point endOne, Point endTwo) {
     this.name = name;
     this.endOne = endOne;
     this.endTwo = endTwo;
     this.intersects = new NoRoad2();
   }

  //ellis2.addIntersection(s55th2) -> void
  // -> ((Larger)ellis2.intersects).first == s55th2
  //Causes this road to intersect r
  //Note: modifies intersects for this
  void addIntersection( Road2 r ) {
    /// this.name ... this.endOne.PointMethod() ... this.endTwo.PointMethod() ... this.intersects.RoadListMethod() 
    this.intersects = new LargerRL2( r, this.intersects );
  }

}

abstract class RoadList2 {
}

class NoRoad2 extends RoadList2 {
}

class LargerRL2 extends RoadList2 {
  Road2 first;
  RoadList2 rest;

  LargerRL2( Road2 first, RoadList2 rest ) {
    this.first = first;
    this.rest = rest;
  }

}


class Map {
  RoadList2 roads;

  Map( RoadList2 roads ) {
    this.roads = roads;
  }

  //Create an intersection between two intersection roads
  //Note: modifies the intersects field of both r and r2
  void createIntersection( Road2 r, Road2 r2 ) {
    r.addIntersection(r2);
    r2.addIntersection(r);
  }
}
/*
Road2 s55th2 = new Road2( "55th", new Point("A",1), new Point("E",1));
Road2 ellis = new Road2("ellis", new Point("A",1), new Point("A",8));

new Map(new NoRoad2()).createIntersection( s55th2, ellis )

ellis

s55th2

*/