//readStu.java  --- you can use this example
import java.io.*;
import java.util.*;
class readStu {
   PrintStream cout=null;
   BufferedReader cin=null;
   Student y[ ];   // all students in y[ ]
   public static final String fileName="studat.txt";
   public static void main(String xxx[ ]) {
      readStu gg = new readStu( );
      gg.prepareIO( );
      gg.main( );
   }
   public readStu( ) { }
   void prepareIO( ) {
       try{
          cout = System.out;
          cin = new BufferedReader(
               new InputStreamReader(System.in) );
       }catch(Exception e) {;}
   }
////////
   int main( ) {
      int nRec = readFile(fileName);
      cout.printf("Total %d students in file %s\n", nRec, fileName);
      printSome(y);
      Arrays.sort(y);
      cout.println(" ==After sort...");
      printSome(y);
      Arrays.sort(y, Collections.reverseOrder( ) );
      cout.println("===After sort with reverseOrder( )...");
      printSome(y);
      return 0;
   }//int main(
   void printSome(Student a[ ]) {
      int i=0;
      for(i=0; i<3; ++i) printOne(a[i], 0);
      cout.println("...");  //////
      int last = a.length;
      for(i= last-3; i < last; ++i) printOne(a[i], 1); //with RANK
   }
/////////
   int readFile(String fn) {
      BufferedReader br=null;
      int nR = 0;
      nR = countRec(fn);
      y = new Student[nR];  // creat array
      try {  // open file
          FileReader fr = new FileReader(fn);
          br = new BufferedReader(fr);
      }catch (Exception e) {;;}
      for(int i=0; i < nR; ++i) {
          y[i] = new Student( );
          String s=null;
          try{
             s = br.readLine( );
          }catch (Exception e) {;;}
          putData(y[i], s);
      }
      return nR;
   }//readFile
   int countRec(String fn) {  // count # of records
       int n = 0;
       try {
          FileReader fr = new FileReader(fn);
          BufferedReader br = new BufferedReader(fr);
          String s = br.readLine( );
          while(s != null) {  // not EOF
             ++n;
             s = br.readLine( );
          }//while(s
          try{if(br!=null)br.close( );}catch(Exception e){;}
       }catch (Exception e) {;;}
       return n;
   }//countRec(
   void putData(Student gg, String s) {
       StringTokenizer stk = new StringTokenizer(s," \t");
       String tmps = stk.nextToken( );
       gg.sid = 0;
       try{ gg.sid = Integer.parseInt(tmps); }catch(Exception e){}
       gg.name = new String(stk.nextToken( ) );
       gg.hwk = 0; tmps = stk.nextToken( );
       try{ gg.hwk = Integer.parseInt(tmps); }catch(Exception e){}
       gg.mid = 0; tmps = stk.nextToken( );
       try{ gg.mid = Integer.parseInt(tmps); }catch(Exception e){}
       //...todo:  quiz, fin 
       gg.total = 0.25 * gg.hwk +0.3*gg.mid+0.1*gg.quiz+0.35*gg.fin;
       gg.rank = 0;
   }//putData(
   void printOne(Student gg, int flag) {  // flag for Rank
       cout.print(" " + gg.sid +"  ");
       cout.printf("%12s ", gg.name);
       cout.printf("%3d %3d %3d %3d ", gg.hwk, gg.mid,
             gg.quiz, gg.fin);
       cout.printf("%6.2f ", gg.total);
       if(flag!=0) cout.printf("%5d", gg.rank);
       cout.println( );
   }
}//readStu
class Student implements Comparable<Student> {
   public int sid;
   public String name;
   public int hwk, mid, quiz, fin;
   public double total;
   public int rank;
   public int compareTo(Student bb) {
      return sid - bb.sid;  // Ascending on sid
   }//compareTo(
}//Student 
/********************
C:\jtest\struct>javac readStu.java

C:\jtest\struct>java readStu
Total 81493 students in file studat.txt
 9834527          林ZQj  17  60   0   0  22.25
 9840229          簡PUa  57   7   0   0  16.35
 9826528          王BLa  95  70   0   0  44.75
...
 9898491          魏NGk  24  48   0   0  20.40     0
 9898492          錢GTe  34  48   0   0  22.90     0
 9898493          趙GGg  29  60   0   0  25.25     0
 ==After sort...
 9817001          張CZt  64  35   0   0  26.50
 9817002          張PKs  91  58   0   0  40.15
 9817003          魏OBa   9  16   0   0   7.05
...
 9898491          魏NGk  24  48   0   0  20.40     0
 9898492          錢GTe  34  48   0   0  22.90     0
 9898493          趙GGg  29  60   0   0  25.25     0
===After sort with reverseOrder( )...
 9898493          趙GGg  29  60   0   0  25.25
 9898492          錢GTe  34  48   0   0  22.90
 9898491          魏NGk  24  48   0   0  20.40
...
 9817003          魏OBa   9  16   0   0   7.05     0
 9817002          張PKs  91  58   0   0  40.15     0
 9817001          張CZt  64  35   0   0  26.50     0

C:\jtest\struct>
******************************************************/