====== Task 1 - EN - Path Planning ======

Create an algorithm which finds a path on the road graph of United Kingdom (UK) between two nodes (intersections).

===== Assignment =====

**Input**:

  * Graph representing road network in UK	
    * The graph edges contain length of the edge and maximal allowed speed
    * The nodes are signed with unique identifier ID.
  * Initial node 
  * Goal node

**Output**:
  * A path between the initial and the goal node

**Quality criteria**, listed in descending priority:
  * The algorithm fulfills all parts of the assignment (classes name and location, using given structures and the method add() in the open list - see below)
  * The path is correct, i.e., leads from origin to destination, the path is connected, i.e., two subsequent edges have a common node and the edges are sorted correctly.
  * The found path minimizes transport time between initial and goal state 
  * The number of expanded nodes is minimal

**Grading**
  - Algorithm fulfills the assignment completely
  - The path is correct, i.e., leads from origin to destination, the path is connected, i.e., two subsequent edges have a common node and the edges are sorted correctly. [+1b]
  - The found path minimizes transport time between initial and goal state   [+2b]
  - The number of expanded nodes is minimal [+0-3b]
===== Submission =====
  * **Date/time**:  25/03/2018 23:59:59
  * **Content**: compressed content of Java package ''student'' (pack only .java source files, no subfolders please)

===== Implementation details =====
  * Use the codebase available {{courses:b4b36zui:astar-bundle.zip|HERE}}.
  * Implement class ''Planner'' in package ''student'' (implementation of the interface ''PlannerInterface'')
  * Create class ''OpenList'' which extends class ''AbstractOpenList'' in your package. **For adding the items to OpenList use only the method add(T item)**
  * If you modify any item in OpenList (you have added it to the OpenList earlier, you just recompute its cost), then you don't need to call the **add** method (however, you can - the Counter value is going to be increased though).
  * The algorithm is going to return **null** if the path does not exist

===== Some code you can use =====
  * The class **RoadGraph** allows you to access the graph and contains a set of method which you can use to move along the graph
  * The class **GraphEdge** contains the methods getAllowedMaxSpeedInKmph() and getLengthInMetres() which return the maximal allowed speed in km and length in meters respectively.
  * The class **Utils** gives you the metric for counting the distance between any two nodes in the graph.
  * The class **PlannerExecutor** allows the body of the program where you can test your algorithm. 

===== Example results =====

=== Solution 1 ===
  * Origin node ID = 13823646
  * Destination node ID = 188755778
  * Plan length [km]: 932.8542488743733
  * Time to travel [hrs]: 12.084881006921961

=== Solution 2 ===
  * Origin node ID = 26746953
  * Destination node ID = 1037726044
  * Plan length [km]: 664.3940259558422
  * Time to travel [hrs]: 8.002850863827378

=== Solution 3 ===
  * Origin node ID = 243081231
  * Destination node ID = 21728749
  * Plan length [km]: 560.2105619356079
  * Time to travel [hrs]: 7.149357704368445