trips.num 
          - contains the numerical represantation fo the instance 
          - format [x1, y1, x2, y2]
          - 4 tupel, first two number are coordinates of the origin
            and number 3 and 4 are the coordinates of the destination

          - the first line is the depot

trips.dat 
          - description with coordinate system from the slides 
          - trip 0  identifies the depot
          - format [no y1 x1 y2 x2]