Clustering problem

ClusterB.java

import java.util.*;
import java.io.File;
public class ClusterB {
    int n;
    int bitsn;
    int clusters ;
    HashMap<String,Nodes> cl = new HashMap<>();
    void getInput() {
        try {
            File f = new File("C:\\Users\\vinir_000\\IdeaProjects\\Learn\\src\\input.txt");
            Scanner sc = new Scanner(f);
            //Scanner sc = new Scanner(System.in);
            n = sc.nextInt();
            bitsn = sc.nextInt();
            clusters = n;
            sc.nextLine();
            for (int i = 0; i < n; i++) {
                String s = sc.nextLine().replaceAll("\\s+", "");
                if (!cl.containsKey(s)) {
                    Nodes n = new Nodes(s);
                    cl.put(s, n);
                }
                //else System.out.println("I am present man");
            }
            clusters = cl.size();
        }
        catch(Exception e){}
    }

    void compute()
    {
        //generate all the nodes at distances 1
        for(String s : cl.keySet())
        {
            for(int i=0;i<bitsn;i++ )
            {
                StringBuilder x = new StringBuilder(s);
                if(x.charAt(i) == '1' )
                    x.setCharAt(i,'0');
                else
                    x.setCharAt(i,'1');

                String y = new String(x.toString());
                merge(s,y);
            }
        }
        //generate all the nodes at distances 2
        for(String s : cl.keySet())
        {
            for(int i=0;i<bitsn-1;i++ )
            {
                for(int j=i+1;j<bitsn;j++)
                {
                    StringBuilder x = new StringBuilder(s);
                    if (x.charAt(i) == '1')
                        x.setCharAt(i, '0');
                    else
                        x.setCharAt(i, '1');

                    if (x.charAt(j) == '1')
                        x.setCharAt(j, '0');
                    else
                        x.setCharAt(j, '1');

                    String y = new String(x.toString());
                    merge(s, y);
                }
            }
        }
    }

    void merge(String x,String y)
    {
        if(cl.containsKey(y))
        {
            Nodes xp = getParent(x);
            Nodes yp = getParent(y);
            if(xp != yp) {
                int xr = xp.rank;
                int yr = yp.rank;
                if (xr > yr)
                    yp.parent = xp;
                else if (xr < yr)
                    xp.parent = yp;
                else {
                    yp.parent = xp;
                    xp.rank = xp.rank + 1;
                }
                clusters--;

            }
            //System.out.println(clusters);

        }
    }

    Nodes getParent(String x)
    {
        if(cl.get(x).parent == cl.get(x))
            return cl.get(x);
        cl.get(x).parent = getParent(cl.get(x).parent.s);
        return cl.get(x).parent;
    }

    public static void main(String args[]) {
        ClusterB cb = new ClusterB();
        cb.getInput();
        cb.compute();
        System.out.print(cb.clusters);
    }
}

class Nodes
{
    String s;
    Nodes parent ;
    int rank = 0;
    Nodes(String s)
    {
        rank = 0;
        this.s = s;
        parent = this;
    }
}