The files containing the drayage instances (Crane100xxx and Crane300xxx) have the following format:

NOMBRE: <name of the instance>
COMENTARIO: <comment>
VERTICES: <number of vertices>
ARCOS_REQ: <number of required arcs>
ARCOS_NOREQ: <number of non-required arcs>
VERTICES_REQ: 0
LIST OF REQUIRED ARCS:
(<u1>,<u2>) coste <c>
.
.
.
LIST OF NO REQUIRED ARCS:
(<u1>,<u2>) coste <c> -1
.
.
.
Cordenadas vertices
<v1> (<x1>,<y1>)
<v2> (<x2>,<y2>)
.
.
.


Entries <name of instance> and <comment> may be empty.
For each required arc from node u1 to node u2 there is a line 

	(<u1>,<u2>) coste <c>

where c is the cost of traversing the arc. 

For each non-required arc from node u1 to node u2 there is a line 

	(<u1>,<u2>) coste <c> -1

where c is the cost of traversing the arc.

There are no required vertices in these instances. The coordinates of the vertices
are given at the end of the file as:

	<v1> (<x1>,<y1>)

where <v1> is the number of the vertex and <x1> and <y1> its coordinates.



The files containing the SCP grid instances (Crane_gridxxx) have a similar format. 
All the vertices not incident with a required arc are non-required vertices.

NAME: <name of the instance>
Arcos no requeridos finales: <number of total non-required arcs>
VERTICES: <number of vertices>
ARCOS_REQ: <number of required arcs>
ARCOS_NOREQ: <number of lines containing the non-required arcs>
VERTICES_REQ: 0
LIST OF REQUIRED ARCS:
(<u1>,<u2>) coste <c>
.
.
.
LIST OF NO REQUIRED ARCS :
(<u1>,<u2>) coste <c1> <c2>
.
.
.
VERTICES REQUE:

The line "Arcos no requeridos finales" gives the total number of non-required arcs of the graph,
while the line "ARCOS_NOREQ:" gives the total number of lines in which the non-required arcs are
given (since some non-required arcs exist in both directions, this number may be smaller than
the total number of arcs).

For each required arc from node u1 to node u2 there is a line 

	(<u1>,<u2>) coste <c>

where c is the cost of traversing the arc. 

For each non-required arc from node u1 to node u2 there is a line 

	(<u1>,<u2>) coste <c1> <c2>

where c1 is the cost of traversing the arc from u1 to u2, and c2 is the cost of traversing it
from u2 to u1, or -1 if such arc does not exist.