Poj Solution 2501

http://poj.org/problem?id=2501

//* @author 
import java.io.*; 
import java.util.*; 
import java.text.DecimalFormat; 

public class Main 
{ 
    static int hh; 
    static int mm; 
    static int ss; 
    static double sumDist; 
    static double speed; 
    public static void main(String[] args) throws Exception 
    { 
        readFile(); 
    } 

    static void readFile() throws Exception 
    { 
        BufferedReader br = new BufferedReader( 
            //new FileReader("in.in")); 
            new InputStreamReader(System.in)); 
        StringTokenizer st = null; 
        String stemp = null; 
        while((stemp=br.readLine())!=null) 
        { 
            st = new StringTokenizer(stemp," "); 
            if(st.countTokens()==2) 
            { 
                stemp = st.nextToken(); 
                double tempspeed = Double.valueOf(st.nextToken()) / 3600; 
                st = new StringTokenizer(stemp,":"); 
                process(Integer.valueOf(st.nextToken()), 
                    Integer.valueOf(st.nextToken()), 
                    Integer.valueOf(st.nextToken()),-1); 
                speed = tempspeed; 
            } 
            else 
            { 
                st = new StringTokenizer(st.nextToken(),":"); 
                process(Integer.valueOf(st.nextToken()), 
                    Integer.valueOf(st.nextToken()), 
                    Integer.valueOf(st.nextToken()),1); 
            } 
        } 
    } 
    static int fff = 0; 
     
    static void process(int h,int m,int s,int flag) 
    { 
        int sumSecond = 0; 
        sumSecond += (s-ss); 
        sumSecond += ((m-mm)*60); 
        sumSecond += ((h-hh)*3600); 
        sumDist += (sumSecond * speed); 
        if(flag==1) 
        { 
            if(fff!=0) 
                System.out.println(); 
            fff++; 
            display(h,m,s); 
            System.out.print(saveDigit(sumDist,2)); 
            System.out.print(" km"); 
        } 
        hh = h; 
        mm = m; 
        ss = s; 
    } 
     
    static String saveDigit(double d,int n) 
    { 
        StringBuffer sb = new StringBuffer("###."); 
        for(int i=0; i< n; i++) 
            sb.append("0"); 
        DecimalFormat df2  = new DecimalFormat(sb.toString()); 
        StringBuffer result = new StringBuffer(df2.format(d)); 
        if(result.indexOf(".")==0) 
            result.insert(0,"0"); 
        return result.toString(); 
    } 
     
    static void display(int h,int m,int s) 
    { 
        if(h< 10) 
            System.out.print("0"); 
        System.out.print(h+":"); 
        if(m< 10) 
            System.out.print("0"); 
        System.out.print(m+":"); 
        if(s< 10) 
            System.out.print("0"); 
        System.out.print(s+" "); 
    } 
}