Greedy Algorithms

Here

$$

s a problem that occurs in automatic program analysis. For a set of variables x

$1$

$,$

$.$

$.$

$.$

$,$

$$xn

$,$

$$you

are given some equality constraints, of the form

$$

xi

$=$

$$xj

$$

$$and some disequality constraints, of the

form

$$

xi

$!$

$=$

$$xj

$.$

$$

$$Is it possible to satisfy all of them?

For instance, the constraints