c = [1 2 5 2 1 2 1]
 
A = [1 1 0 0 0 0 0;
     0 0 1 1 0 0 0;
     0 0 0 0 1 1 1;
     1 0 0 0 1 0 0;
     0 1 0 0 0 0 0;
     0 0 1 0 0 1 0;
     0 0 0 1 0 0 1]

b = [ 200;
     1000;
     1000;
     1100;
      200;
      500;
      500]