UVa Problem ID 10683 (The decadary watch)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	 public static void main(String[] args) throws IOException 
	    {
	        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	        String input;
	        StringBuffer sb=new StringBuffer("");
	       
	        while((input=br.readLine())!=null)
	        {
	        	int HH=Integer.parseInt(input.substring(0,2));
	        	int MM=Integer.parseInt(input.substring(2,4));
	        	int SS=Integer.parseInt(input.substring(4,6));
	        	int CC=Integer.parseInt(input.substring(6));
	        	if(HH<0 || HH>59 || MM<0 || MM>59 || SS<0 || SS>59 || CC <0 || CC>99)
	        		break;
	        	//System.out.println("HH ="+HH+" MM="+MM+" SS="+SS+" CC="+CC);
	        	int decimaltimestring=(HH*360000+MM*6000+SS*100+CC)*125/108;
	        	StringBuffer s=new StringBuffer(decimaltimestring+"");
	        	if(s.length()<7)
	        	{
	        		while (s.length()!=7) {
						s.insert(0,'0');
					}
	        	}
	        	sb.append(s);
	        	sb.append("\n");
	        }
	        System.out.print(sb);
	    }
}