Find a Four-Coloring of a Map of Europe 

Find the neighbors of each European country.

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These are the neighbors of Austria.

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Encode the four possible colors as two Booleans per country.

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Express the condition that all pairs of bordering countries have different colors as a logical expression.

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Compute a solution to the four-color problem.

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Form the coloring.

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Color each country according to the coloring found.

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