! California Manufacturing Company 

MAX  9 x1 + 5 x2 + 6 x3 + 4 x4
s.t.
      6 x1 + 3 x2 + 5 x3 + 2 x4 <= 10.0
                      x3 +   x4 <=    1
      - x1        +   x3        <=    0
             - x2        +   x4 <=    0
END
! All the variables are binary integers;
INT 4

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