// Allison Obourn
// CSE 143 - lecture 12
// Outputs a list of TAs by grade.
// It demonstrates using a Map mapping something to another collection.

import java.util.*;
import java.io.*;

public class TAgrades {
   public static void main(String[] args) throws FileNotFoundException {
      
      Scanner input = new Scanner(new File("tas.txt"));
      Map<Double, Set<String>> grades = new TreeMap<Double, Set<String>>();

      // puts all the grades in the map connected to tas
      while(input.hasNext()) {
         String ta = input.next().toLowerCase();
         double grade = input.nextDouble();
         if(!grades.containsKey(grade)){
            grades.put(grade, new TreeSet<String>());  
         }
         grades.get(grade).add(ta);
      }
      
      // removes grades below a 3.0
      Iterator<Double> itr = grades.keySet().iterator();
      while(itr.hasNext()) {
         double grade = itr.next();
         if(grade < 3.0) {
            itr.remove();
         }
      }
      
      // iterate over the map using the set of keys
      for(Double grade : grades.keySet()) {
         System.out.println(grade + " " + grades.get(grade));
      }
   }
}