Hi friend,

import java.io.*;
import java.util.HashMap;
import java.util.Map;
import java.util.*;
public class ReadLine {

public static void main(String[] args) throws Exception {
InputStreamReader isr = new InputStreamReader(System.in);
BufferedReader bufReader = new BufferedReader(isr);
System.out.println("Enter the number Student less then or equal to 50");
int studentNo = Integer.parseInt(bufReader.readLine());
Map map = new HashMap();
int score=0;
String studentName;
for(int i=1;i<=studentNo;i++)
{
System.out.println("Enter the Student");
studentName = bufReader.readLine().toString();
System.out.println("Enter the Score");
score = Integer.parseInt(bufReader.readLine());
map.put(score, studentName);
}
Iterator iterator = map.keySet().iterator();
int sum=0;
int max=0;
while( iterator. hasNext() ){
int s = Integer.parseInt(iterator.next().toString().trim());
if(max<s)
{
max=s;
}
sum+=s;
}
int totalsutdent = map.size();
int avg=Math.round(sum/totalsutdent);
System.out.println("avg " + avg);
System.out.println("max " + max);
Iterator lowItr = map.keySet().iterator();
String lowStudent="";
String highStudent="";
while(lowItr.hasNext()){
int sval= Integer.parseInt(lowItr.next().toString().trim());
if(sval<avg)
{
lowStudent+=map.get(sval)+",";
}
if(max==sval)
{
highStudent+=map.get(sval)+",";
}
}
System.out.println("Students whose test scores are below the class average = " + avg );
System.out.println( lowStudent.substring(0,lowStudent.lastIndexOf(",")));
System.out.println("Students whose test scores are highest = " + max );
System.out.println("" + highStudent.substring(0,highStudent.lastIndexOf(",")));
}
}


For read more information :
http://www.roseindia.net/java/

Thanks