trains

                o    .  o  .  o .  o  .  o  .  o
           o
        .
      .        ___
     _n_n_n____i_i ________ ______________ _++++++++++++++_
  *>(____________I I______I I____________I I______________I
    /ooOOOO OOOOoo  oo oooo oo          oo ooo          ooo
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