nodes.png


    6 ++--------+---------+---------+---------+---------+---------+--------++
      +         +         +         +  .      +         +"nodes.dat"   .    +
      |                       .                      .                      |
  5.5 ++                            .                  .       .           ++
      |                                                                     |
      |                                                                     |
      |                                                                     |
    5 ++                      .                                 .          ++
      |                                                    .                |
      |                                                                     |
  4.5 ++                 .                              . .    .           ++
      |           .       .  .              .                               |
      |                 .         .                                         |
    4 ++      .    . .    .                                                ++
      |                                                                     |
      |                              .                                      |
      |                                                              .      |
  3.5 ++                                                                   ++
      |                                                                     |
      +         +         +         +         +         +         +   . .   +
    3 ++--------+---------+---------+---------+---------+---------+--------++
      2         3         4         5         6         7         8         9