A toy project demonstrating how to solve the N Queens puzzle using Kotlin with the popular open source Java-based OptaPlanner constraint solver and the Drools rule engine.
This code is meant to be used for demonstration and learning purposes; multicore, parallel and even polynomial time solutions [0] are readily available elsewhere.
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2018-07-20 12:30:34,319 INFO [main] DefaultSolver: Solving ended: time spent (798), best score (0), score calculation speed (31239/sec), phase total (2), environment mode (REPRODUCIBLE).
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2018-07-20 12:30:34,319 INFO [main] optaplanner: Done
[0] Rok Sosic and Jun Gu. 1990. A polynomial time algorithm for the N-Queens problem. SIGART Bull. 1, 3 (October 1990), 7-11. DOI=http:https://dx.doi.org/10.1145/101340.101343