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The.Algorithm.Design.Manual.Springer-Verlag.1998

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Lecture 20 - integer programming<br />

Example:<br />

A solution to this is , .<br />

Example:<br />

Since the maximum value of f(v) given the constraints is , there is no solution.<br />

<strong>The</strong>orem: Integer Programming is NP-Hard<br />

Proof: By reduction from Satisfiability<br />

Any set instance has boolean variables and clauses. Our Integer programming problem will have twice as<br />

many variables as the SAT instance, one for each variable and its compliment, as well as the following<br />

inequalities:<br />

Listen To Part 24-4<br />

For each variable in the set problem, we will add the following constraints:<br />

● and<br />

●<br />

Both IP variables are restricted to values of 0 or 1, which makes them equivalent to boolean<br />

variables restricted to true/false.<br />

Exactly one of the IP variables associated with a given sat variable is 1. This means that exactly<br />

one of and are true!<br />

file:///E|/LEC/LECTUR16/NODE20.HTM (2 of 4) [19/1/2003 1:35:24]

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