Really old Trainyard puzzle example

TrainyardPuzzleExample.xml

<grid rows="7" cols="7">
  <pieces>
    <destination pos="0,0" sides="r" colors="p"/>
    <splitter pos="3,0" side="b"/>
    <station pos="6,0" side="l" colors="o"/>
    <factory pos="0,3" sides="tb" color="r"/>
    <rock pos="1,3"/>
    <rock pos="2,3"/>
    <rock pos="3,3"/>
    <rock pos="4,3"/>
    <rock pos="5,3"/>
    <factory pos="6,3" sides="tb" color="b"/>
    <station pos="0,6" side="r" colors="o"/>
    <splitter pos="3,6" side="t"/>
    <destination pos="6,6" sides="l" colors="p"/>
  </pieces>
</grid>