working

src/Model.h

@@ -20,7 +20,5 @@ struct Customer
 
 struct Cost
 {
-    Customer m_Customer;
-    Facility m_Facility;
-    int m_Cost;
+    double m_Cost;
 };

src/Parser.cpp

@@ -49,16 +49,19 @@ FileData ParseFile(const std::string& a_FileName) {
 		fileData.m_Customers.push_back(customer);
 	}
 
+	fileData.m_Costs.resize(fileData.m_Customers.size());
+	for (std::size_t i = 0; i < fileData.m_Customers.size(); i++) {
+		fileData.m_Costs[i].resize(fileData.m_Facilities.size());
+	}
+
 	// costs
 	while (getline(in, line))
 	{
-		Cost cost;
+		double cost;
 		int facilityID, customerID;
 		std::stringstream stream(line);
-		stream >> customerID >> facilityID >> cost.m_Cost;
-		cost.m_Customer = fileData.m_Customers[customerID - 1];
-		cost.m_Facility = fileData.m_Facilities[facilityID - 1];
-		fileData.m_Costs.push_back(cost);
+		stream >> customerID >> facilityID >> cost;
+		fileData.m_Costs[customerID - 1][facilityID - 1] = cost;
 	}
 
 	return fileData;

src/Parser.h

@@ -7,7 +7,7 @@ struct FileData
 {
 	std::vector<Facility> m_Facilities;
 	std::vector<Customer> m_Customers;
-	std::vector<Cost> m_Costs;
+	std::vector<std::vector<double>> m_Costs;
 };
 
 FileData ParseFile(const std::string& a_FileName);

src/main.cpp

@@ -1,56 +1,91 @@
 #include "Parser.h"
-#include <fmt/format.h>
 #include <iostream>
-#include <kiwi/kiwi.h>
 
-using namespace kiwi;
+#include <absl/base/log_severity.h>
+#include <absl/log/globals.h>
+#include <absl/log/log.h>
+#include <ortools/base/init_google.h>
+#include <ortools/sat/cp_model.h>
+#include <ortools/sat/cp_model_solver.h>
+
+#include <chrono>
+
+using namespace operations_research;
 
 int main(int argc, char** argv) {
 	auto fileData = ParseFile("RhoneCities_100.flpb");
 
-	std::vector<Variable> y;
-	std::vector<std::vector<Variable>> x(fileData.m_Facilities.size());
+	sat::CpModelBuilder cp_model;
+
+	std::vector<sat::BoolVar> y;
+	std::vector<std::vector<sat::BoolVar>> x(fileData.m_Customers.size());
 
 	std::cout << "Adding variables ...\n";
-	Solver solver;
 
 	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
-		y.emplace_back(fmt::format("y_{}", j));
+		y.push_back(cp_model.NewBoolVar());
 		for (std::size_t i = 0; i < fileData.m_Customers.size(); i++) {
-			x[i].emplace_back(fmt::format("x_{}{}", i, j));
+			x[i].push_back(cp_model.NewBoolVar());
 		}
 	}
 
 	std::cout << "Adding constraints 1...\n";
 	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
-		Expression sum;
+		sat::LinearExpr sum;
 
-		for (std::size_t i = 0; i < fileData.m_Customers.size(); i++) {
-			sum = sum + fileData.m_Customers[i].m_Demand * x[i][j];
+		for (size_t i = 0; i < fileData.m_Customers.size(); i++) {
+			sum += fileData.m_Customers[i].m_Demand * x[i][j];
 		}
 
-		solver.addConstraint({sum <= fileData.m_Facilities[j].m_Capacity * y[j]});
+		cp_model.AddLessOrEqual(sum, fileData.m_Facilities[j].m_Capacity * y[j]);
 	}
 
 	std::cout << "Adding constraints 2...\n";
 	for (std::size_t i = 0; i < fileData.m_Customers.size(); i++) {
-		Expression sum;
+		cp_model.AddEquality(sat::LinearExpr::Sum(x[i]), 1);
+	}
 
-		for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
-			sum = sum + x[i][j];
+	sat::DoubleLinearExpr obj;
+
+	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
+		for (size_t i = 0; i < fileData.m_Customers.size(); i++) {
+			auto cost = fileData.m_Costs[i][j];
+			obj += cost * sat::DoubleLinearExpr(x[i][j]);
 		}
-
-		solver.addConstraint({sum == 1});
 	}
 
-	std::cout << "Updating variables...\n";
-	solver.updateVariables();
-
-	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++)
-	{
-		std::cout << y[j].name() << "=" << y[j].value() << "\n";
+	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
+		obj += fileData.m_Facilities[j].m_Cost * sat::DoubleLinearExpr(y[j]);
 	}
-	
+
+	cp_model.Minimize(obj);
+
+	std::cout << "Solving...\n";
+
+	auto start = static_cast<std::uint64_t>(
+		std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock().now().time_since_epoch()).count());
+
+	auto solution = sat::Solve(cp_model.Build());
+
+	auto end = static_cast<std::uint64_t>(
+		std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock().now().time_since_epoch()).count());
+
+	std::cout << "Done in " << end - start << "ms !" << std::endl;
+	std::cout << "Status : " << solution.status() << std::endl;
+	std::cout << "Objective : " << solution.objective_value() << "€" << std::endl;
+
+	int fac_number = 0;
+
+	for (std::size_t j = 0; j < fileData.m_Facilities.size(); j++) {
+		bool make_fac = sat::SolutionBooleanValue(solution, y[j]);
+		std::cout << make_fac;
+		if (make_fac)
+			fac_number++;
+	}
+
+	std::cout << std::endl;
+
+	std::cout << "N=" << fac_number << std::endl;
 
 	return 0;
 }

xmake.lua

@@ -1,12 +1,11 @@
 add_rules("mode.debug", "mode.release")
 
-add_requires("kiwisolver", "fmt")
-
--- https://github.com/Qix-/kiwi/blob/int-solver/kiwi/variable.h
+add_requires("or-tools[highs=true,glpk=true]")
 
 target("RhoneCities")
     set_kind("binary")
-    add_packages("kiwisolver", "fmt")
+    add_defines("OR_PROTO_DLL=")
+    add_packages("or-tools")
     add_files("src/*.cpp")
     set_rundir(".")