// CSE 143, Autumn 2015

// This program demonstrates the use of stacks and queues.
// It reads in a file of students' exam scores in reverse order, such as:
//
// Zahn           William        92
// Yu             Vivian         95
// Wolf           Adam           87
// 
// And first strips the ones who got 100 on the exam using a queue,
// then prints the rest in reverse order using a stack.

// WARNING: this is an example of how to use stacks and queues, 
//          not an example of good code. 

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

public class Exams {
   public static void main(String[] args) throws FileNotFoundException {
	   	   
	   Scanner input = new Scanner(new File("ta.txt"));
      
      Queue<String> tas = new LinkedList<String>();
      
      // read the lines from the file (in reverse ABC order) into a queue
      while(input.hasNextLine()) {
         tas.add(input.nextLine());
      }  
      
      // filter out the students who got 100 on the exam
      // WARNING: we wrote the code this way as a demonstartion of how to loop
      //          through a queue. In your homework and other coding you should
      //          combine loops when possible and not write them like this.
      int size = tas.size();
      for(int i = 0; i < size; i++) {
         String ta = tas.remove();
         if(!ta.endsWith("100")) {
            tas.add(ta);
         }
      }   
    
      // move all of the tas to a stack to reverse them
      Stack<String> reverse = new Stack<String>();
      while(!tas.isEmpty()) {
         reverse.push(tas.remove());
      }
      
      // move the tas back to the queue and print them out in 
      // alphabetical order
      while(!reverse.isEmpty()) {
         String ta = reverse.pop();
         System.out.println(ta);
         tas.add(ta);
      }
      
      // restore tas to their original order in the LinkedList
      while(!tas.isEmpty()) {
         reverse.push(tas.remove());
      }  
      
      while(!reverse.isEmpty()) {
         tas.add(reverse.pop());
      }
   }
}