\ Buchberger Algorithm and Integer Programming
\ by Pasqualina Conti and Carlo Traverso
\ http://posso.dm.unipi.it/users/traverso/conti-traverso-ip.ps
Minimize
  x1 + x2 + x3 + x4 + x5
Subject To
  + 2 x1 + 5 x2 - 3 x3 + 1 x4 - 2 x5 = 214
  + 1 x1 + 7 x2 + 2 x3 + 3 x4 + 1 x5 = 712
  + 4 x1 - 2 x2 - 1 x3 - 5 x4 + 3 x5 = 331
Bounds
  0 <= x1 <= +inf
  0 <= x2 <= +inf
  0 <= x3 <= +inf
  0 <= x4 <= +inf
  0 <= x5 <= +inf
General
  x1 x2 x3 x4 x5
End