MDGP Instance format:

The first line has the following fields separed with spaces:
M: Integer indicating the number of elements 
G: Integer indicating the The number of groups
Group Type: The value can be "ss" or "ds" and represent "same size group" or "different size group"
Group limits: The last numbers of the line correspond to the lower and upper limits of each group

The following lines contain the distance between elements with the format:
elementA elementB distance