The instances have the following format:
the first line contains two integer numbers corresponding to the number of items and capacity, respectively.
Then, there is one line for each item, reporting the profit and weight of the item.
The name of each instance provides same features of the instance, e.g. n500C10N125R1000C7.txt
n is the number of items
C is the percentage of the total item weight used to determine the capacity
N is the number of items with negative profit; these are always the first items in the file
R and C rapresent the two input parameter used to generate the KP instance descibed in
''Dynamic programming and tight bounds for the 0-1 Knapsack Problem'' by Martello, Pisinger and Toth
and downloadable at http://www.diku.dk/~pisinger/codes.html