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A dumb introduction to z3
Exploring the world of constraint solvers with very simple examples.
The MiniZinc homepage(another popular solver) has a couple of nice examples: a seating chart, rostering, vehicle routing, grid coloring. To actually extract the values programmatically, instead of debug printing model, requires some song and dance with the API, but it is simple, really. The problem is that Int really spans the entire natural integers range, so it is accounting for negative amounts of coins.
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