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+// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
+/*
+
+ This simple example shows how to call dlib's optimal linear assignment problem solver.
+ It is an implementation of the famous Hungarian algorithm and is quite fast, operating in
+ O(N^3) time.
+
+*/
+
+#include <dlib/optimization/max_cost_assignment.h>
+#include <iostream>
+
+using namespace std;
+using namespace dlib;
+
+int main ()
+{
+ // Let's imagine you need to assign N people to N jobs. Additionally, each person will make
+ // your company a certain amount of money at each job, but each person has different skills
+ // so they are better at some jobs and worse at others. You would like to find the best way
+ // to assign people to these jobs. In particular, you would like to maximize the amount of
+ // money the group makes as a whole. This is an example of an assignment problem and is
+ // what is solved by the max_cost_assignment() routine.
+ //
+ // So in this example, let's imagine we have 3 people and 3 jobs. We represent the amount of
+ // money each person will produce at each job with a cost matrix. Each row corresponds to a
+ // person and each column corresponds to a job. So for example, below we are saying that
+ // person 0 will make $1 at job 0, $2 at job 1, and $6 at job 2.
+ matrix<int> cost(3,3);
+ cost = 1, 2, 6,
+ 5, 3, 6,
+ 4, 5, 0;
+
+ // To find out the best assignment of people to jobs we just need to call this function.
+ std::vector<long> assignment = max_cost_assignment(cost);
+
+ // This prints optimal assignments: [2, 0, 1] which indicates that we should assign
+ // the person from the first row of the cost matrix to job 2, the middle row person to
+ // job 0, and the bottom row person to job 1.
+ for (unsigned int i = 0; i < assignment.size(); i++)
+ cout << assignment[i] << std::endl;
+
+ // This prints optimal cost: 16.0
+ // which is correct since our optimal assignment is 6+5+5.
+ cout << "optimal cost: " << assignment_cost(cost, assignment) << endl;
+}
+