UVa - 446 Kibbles `n' Bits `n' Bits `n' Bits

//java solution
import java.util.*;
import java.util.regex.*;
import java.io.*;
import java.awt.*;
import java.awt.geom.*;
import java.math.*;
import java.text.*;

class Main
{
  

    public static void main (String args[])  // entry point from OS
    {
        Main myWork = new Main();  // create a dynamic instance
        myWork.Begin();            // the true entry point
    }

    void Begin()
    {
        String sa,sb,tsa,tsb,so;long l;
        BigInteger a=new BigInteger("0",16),b=new BigInteger("0",16),c=new BigInteger("0",16);
Scanner sc=new Scanner(new BufferedReader(new InputStreamReader(System.in)));
PrintWriter pr=new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));       
try
 {
          sc=new Scanner(new BufferedReader(new FileReader("INPUT.TXT")));
}
 catch(Exception e)
 {
     System.exit(0);
 }
       
       
   //default delimiter : "\\s+"
            // that means spaces , tabs , newlines(form feeds , carriage returns)
            // are skipped
        l=sc.nextLong();
        for(long i=0;i<l;i++)
        {
            sa=sc.next();so=sc.next();sb=sc.next();
            a=new BigInteger(sa,16);b=new BigInteger(sb,16);
        if(so.compareTo("+")==0)
        {
            c=a.add(b);
        }
        else
        {
            c=a.subtract(b);
        }
        tsa=a.toString(2);tsb=b.toString(2);
        tsa=String.format("%13s",tsa);
        tsb=String.format("%13s",tsb);
        tsa=tsa.replace(' ','0');
        tsb=tsb.replace(' ','0');
        pr.printf("%s %s %s = %s%n",tsa,so,tsb,c.toString(10));
        }
    pr.close();
    sc.close();
    }
}