The problem

               Maximize
                   2x + y
               subject to
                   c1:  x + 4y <= 24
                   c2:       y <=  5
                   c3: 3x +  y <= 20
                   c4:  x +  y <=  9
               and
                   0 <= x,y <= +infinity

and the extra constraint

               c5: 6x + y <= 20

are first stored in the user's data structures. The LP is then loaded into Optimizer, using loadprob, and solved using the primal simplex algorithm. Next, the extra constraint is added to the problem matrix, using addrows, and the revised problem solved using the dual algorithm. In each case, the problem matrix is output to a file, the objective function value displayed on screen, and the problem statistics are are stored in a log file.

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