Brian

1
Code Poets

• Brian
• Buddha (Christian)
• Forest
• Tom
• Will

2
Team Duties

• Brian JavaBot Implementation
• Buddha Debug and Troubleshoot
• Forest C A and Problem Solver
• Tom Java A, Problem Solver, and
• Web Site
• Will Java Code, Problem Solver, and
  Power Point

3
A Algorithm

• A is the most widely known Best-First Search
• Created by Hart, Nilsson, and Raphael
• Optimal and Complete
• F G Heuristic
• OPEN, CLOSED, and PATH containers
• Initial node and goal node

4
A Pseudo Code

• Start with the OPEN container containing only the
  starting node.
• Set starting nodes g value to 0, and its h
  value to the SLD.
• Until the goal node is found
• Choose the Best Node with best the best f
  value from OPEN
• If Best Node is Goal Node, exit,
  otherwise
• Push Best Node onto the CLOSED
  container
• Get all children of Best Node
• For every child of Best Node
• Set childs parent to Best Node (very
  important)
• Calculate the G of every
  child
• Scan OPEN and CLOSED
  container for child
• If child is not on OPEN or
  CLOSED, add it to OPEN

5
A Storing the Path

• The PATH lies in the CLOSED list
• One approach (pseudocode)
• ADD CLOSED.back to PATH
• Remove CLOSED.back from CLOSED
• While CLOSED is NOT EMPTY
• If Parent(CLOSED.back) PATH. back
• Set CLOSED.back as PATH.back
• REMOVE CLOSED.back from CLOSED

6
Examples

SLD to D A 12 B 10 C 7 D 0
A
4
5
C
B
7
D
7
Issues

• NetBeans 4.0 Beta 2
• Framework
• UT2004 Map A and B Oscillation
• Connecting the JavaBot