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Maximize
 obj: x1 + 2 x2 + 3 x3 + x4
Subject To
 c1: - x1 + x2 + x3 + 10 x4 <= 20
 c2: x1 - 3 x2 + x3 <= 30
 c3: x2 - 3.5 x4 = 0
 c4: x6 + x7 + x8 + x9 >= 0
Bounds
 0 <= x1 <= 40
 -2 <= x4 <= 3
 -inf <= x5 <= +inf
 0 <= x6 <= +inf
 -1 <= x7 <= +inf
 -inf <= x8 <= +1
 1 <= x9 <= +inf
General
 x4 x5 x6 x7 x8
SEMI-CONTINUOUS
 x9
End