// // Copyright 2012 Hakan Kjellerstrand // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. using System; using System.Collections; using System.IO; using System.Linq; using System.Text.RegularExpressions; using Google.OrTools.ConstraintSolver; public class Strimko2 { /** * * Solves a Strimko problem. * See http://www.hakank.org/google_or_tools/strimko2.py * */ private static void Solve() { Solver solver = new Solver("Strimko2"); // // data // int[,] streams = {{1,1,2,2,2,2,2}, {1,1,2,3,3,3,2}, {1,4,1,3,3,5,5}, {4,4,3,1,3,5,5}, {4,6,6,6,7,7,5}, {6,4,6,4,5,5,7}, {6,6,4,7,7,7,7}}; // Note: This is 1-based int[,] placed = {{2,1,1}, {2,3,7}, {2,5,6}, {2,7,4}, {3,2,7}, {3,6,1}, {4,1,4}, {4,7,5}, {5,2,2}, {5,6,6}}; int n = streams.GetLength(0); int num_placed = placed.GetLength(0); // // Decision variables // IntVar[,] x = solver.MakeIntVarMatrix(n, n, 1, n, "x"); IntVar[] x_flat = x.Flatten(); // // Constraints // // all rows and columns must be unique, i.e. a Latin Square for(int i = 0; i < n; i++) { IntVar[] row = new IntVar[n]; IntVar[] col = new IntVar[n]; for(int j = 0; j < n; j++) { row[j] = x[i,j]; col[j] = x[j,i]; } solver.Add(row.AllDifferent()); solver.Add(col.AllDifferent()); } // streams for(int s = 1; s <= n; s++) { IntVar[] tmp = (from i in Enumerable.Range(0, n) from j in Enumerable.Range(0, n) where streams[i,j] == s select x[i,j]).ToArray(); solver.Add(tmp.AllDifferent()); } // placed for(int i = 0; i < num_placed; i++) { // note: also adjust to 0-based solver.Add(x[placed[i,0] - 1,placed[i,1] - 1] == placed[i,2]); } // // Search // DecisionBuilder db = solver.MakePhase(x_flat, Solver.INT_VAR_DEFAULT, Solver.INT_VALUE_DEFAULT); solver.NewSearch(db); while (solver.NextSolution()) { for(int i = 0; i < n; i++) { for(int j = 0; j < n; j++) { Console.Write(x[i,j].Value() + " "); } Console.WriteLine(); } Console.WriteLine(); } Console.WriteLine("\nSolutions: {0}", solver.Solutions()); Console.WriteLine("WallTime: {0}ms", solver.WallTime()); Console.WriteLine("Failures: {0}", solver.Failures()); Console.WriteLine("Branches: {0} ", solver.Branches()); solver.EndSearch(); } public static void Main(String[] args) { Solve(); } }