Question

Can I have a bipartite matching java program best solution

Answer 1

import java.util.*;

import java.lang.*;

import java.io.*;

  

class GFG

{

    // P is the number of applicants

    // and Q is the number of jobs

    static final int P = 6;

    static final int Q = 6;

  

    // A DFS recursive function that returns true if a matching for vertex u is possible

    boolean bpm(boolean bpGraph[][], int u, boolean seen[], int matchR[])

    {

        for (int v = 0; v < Q; v++)

        {

            // If applicant u is interested in job v and v is not visited

            if (bpGraph[u][v] && !seen[v])

            {

                  

                // Mark v as visited

                seen[v] = true;

  

                // If job 'v' is not assigned to an applicant or previously assigned applicant for job v (which is matchR[v]) has an //alternate job available. Since v is marked as visited, matchR[v] in the following recursive call will not get the job 'v' again

                if (matchR[v] < 0 || bpm(bpGraph, matchR[v],

                                         seen, matchR))

                {

                    matchR[v] = u;

                    return true;

                }

            }

        }

        return false;

    }

  

    //It will return the maximum number of matching from M to N

    int maxBPM(boolean bpGraph[][])

    {

        // Creating an  array to keep track of the  applicants assigned to jobs. The value of matchR[i] is the applicant number //assigned to job i, the value -1 indicates nobody is assigned .

        int matchR[] = new int[N];

  

        // Initially all jobs are available to be assigned

        for(int i = 0; i < Q; ++i)

            matchR[i] = -1;

  

        // It will store the count of jobs assigned to applicants

        int result = 0;

        for (int u = 0; u < P; u++)

        {

            // Mark all jobs as not seen for next applicant.

            boolean seen[] =new boolean[Q] ;

            for(int i = 0; i < Q; ++i)

                seen[i] = false;

  

            // Find if 'u' can get a job

            if (bpm(bpGraph, u, seen, matchR))

                result++;

        }

        return result;

    }

  

  

    public static void main (String[] args) throws java.lang.Exception

    {

        // Let us create a bpGraph

        boolean bpGraph[][] = new boolean[][]; // assign 6*6 i.e. 36 values to the bpGraph

        GFG m = new GFG();

        System.out.println( "Maximum number of applicants that can get job is "+ m.maxBPM(bpGraph));

    }

}