! Nemhauser & Wolsey, 2. "B&B using LP relaxations"
! Exa. 2.2, p 363 z* = 176, X=[0 1 0 1 1 0 1 1 0]
Maximize 77 x1 + 6 x2 + 3 x3 + 6 x4 + 33 x5 + 13 x6 + 110 x7 + 21 x8 + 47 x9
st
 774 x1 + 76 x2 + 22 x3 + 42 x4 + 21 x5 + 760 x6 + 818 x7 + 62 x8 + 785 x9 < 1500
  67 x1 + 27 x2 +794 x3 + 53 x4 +234 x5 +  32 x6 + 797 x7 + 97 x8 + 435 x9 < 1500
 x1 < 1
 x2 < 1
 x3 < 1
 x4 < 1
 x5 < 1
 x6 < 1
 x7 < 1
 x8 < 1
 x9 < 1
end