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Data format

The presented instances are stored in two basic formats. We generally assume that n is the number of facilities and m the number of cities.

1. ORLIB-cap format

In the ORLIB-cap format it is possible to store instances for the uncapacitated and capacitated facility location problem. The first line of a file consists n and m:
[n] [m]
Then the next n lines consist of the opening cost and the capacity of the corresponding facility.
So for each facility i: (i = 1 ,..., n):
[capacity] [opening cost]
In the following the numbers for the cities are the demand and the connections to all facilities.
So for each city j (j = 1, ... ,m):
[demand of j]
[cost of allocating all demand of j to facility i] (i = 1,...,n)

Example: uncapacitated n = 4, m = 3
4 3
0 300
0 400
0 150
0 200
0
130 140 130 100
0
120 100 90 120
0
80 50 140 150

2. Simple format

The simple format is only suitable for instances of the uncapacitated facility location problem.
The first line consists of 'FILE: ' and the name of the file. In the next line n, m and 0 are denoted:
[n] [m] 0
The next n lines consist of the number of the facility, the opening cost and the connetion cost to the cities.
So for facility i (i = 1, ... , n) we have
[i] [opening cost] [cost of conneting city j to facility i] (j = 1, ... ,m)

Example: n = 4, m = 3
FILE: Exapmle.txt
4 3 0
1 300 130 120 80
2 400 140 100 50
3 150 130 90 140
4 200 100 120 150

3. Solution format

The data-format of the solutions is very simple. At first there are m numbers in the range of [0,n-1]. The i-th number is the facility city i is connected to. The last number of the file is the cost of the solution. Facilities and cities are ordered by the appearance in the problem file. If the number of a facility does not appear in the solution file, it remains closed in the solution. Please note that the numbering starts with 0 here !

Example: n = 4, m = 3
2 2 2 510