org.apache.hadoop.examples.dancing
Class DistributedPentomino

java.lang.Object
  org.apache.hadoop.conf.Configured
      org.apache.hadoop.examples.dancing.DistributedPentomino

All Implemented Interfaces:

Configurable, Tool

public class DistributedPentomino
extends Configured
implements Tool

Launch a distributed pentomino solver. It generates a complete list of prefixes of length N with each unique prefix as a separate line. A prefix is a sequence of N integers that denote the index of the row that is choosen for each column in order. Note that the next column is heuristically choosen by the solver, so it is dependant on the previous choice. That file is given as the input to map/reduce. The output key/value are the move prefix/solution as Text/Text.

Nested Class Summary

static class

DistributedPentomino.PentMap Each map takes a line, which represents a prefix move and finds all of the solutions that start with that prefix.

Constructor Summary

DistributedPentomino()

Method Summary

static void	main(String[] args) Launch the solver on 9x10 board and the one sided pentominos.
int	run(String[] args) Execute the command with the given arguments.

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.hadoop.conf.Configurable

getConf, setConf

Constructor Detail

DistributedPentomino

public DistributedPentomino()

Method Detail

main

public static void main(String[] args)
                 throws Exception

Launch the solver on 9x10 board and the one sided pentominos. This takes about 2.5 hours on 20 nodes with 2 cpus/node. Splits the job into 2000 maps and 1 reduce.

Throws:

Exception

run

public int run(String[] args)
        throws Exception

Description copied from interface: Tool

Execute the command with the given arguments.

Specified by:

run in interface Tool

Parameters:

args - command specific arguments.

Returns:

exit code.

Throws:

Exception