IP2
Balas Additive Algorithm for Binary Integer Programming
We will use the Balas Additive Algorithm to solve the following problem:
- Minimize: Z = 3 x₁ + 5 x₂ + 6 x₃ + 9 x₄ + 10 x₅ + 10 x₆
Subject to:
- (1) -2 x₁ + 6 x₂ - 3 x₃ + 4 x₄ + x₅ - 2 x₆ ≥ 2
- (2) -5 x₁ - 3 x₂ + x₃ + 3 x₄ - 2 x₅ + x₆ ≥ - 2
- (3) 5 x₁ - x₂ + 4 x₃ - 2 x₄ + 2 x₅ - x₆ ≥ 3
- and xj binary for j = 1, 2,....6
Recall that the Balas Additive Algorithm uses the depth-first node selection strategy.
Also, notice that the terms in the objective function are written in increasing order, and that it is a minimization problem. So having x₁=0 and x₂=1 is worse than having x₁=1 and x₂=0, etc.