import java.util.Comparator;

import java.util.ArrayList;

import java.io$.$IOException;

import java.util.Scanner;

import java.io$.$FileReader;

public class HuffmanCodeGenerator

$\{$

$/**$

$*$ Generates a table with a list of codewords

$*$ @param codeList the list of codes

$*$ @return an array list sorted by symbols in ascending order

$*/$

public static ArrayList genTable$($ArrayList codeList$)$ throws PQueueException

$\{$

$//$Implement this method

return null;

$\}$

$/**$

$*$ Generates Huffman codes given the root of a Huffman Tree

$*$ @param root the root of a Huffman Tree

$*$ @return an ArrayList containing SymData objects

$*/$

public static ArrayList genHuffCodes$($SymData root$)$ throws PQueueException

$\{$

$//$Implement this method

return null;

$\}$

$/**$

$*$ Generates a binary Huffman Tree

$*$ @param huffForest a forest of SymData objects

$*$ @return a reference to the root of the Huffman tree

$*/$

public static SymData genHuffTree$($PQueue huffForest$)$ throws PQueueException

$\{$

$//$Implement this method

return null;

$\}$

public static void main$($String$[]$ args$)$ throws IOException

$\{$

try

$\{$

String usage $=$ "HuffmanCodeGenerator $\%$n$"$;

usage $+=$ "The data file name is entered as a command line argumet.$\%$n$"$;

usage $+=$ "The data file contains two columns per row.$\%$n$"$;

usage $+=$ "Each row has a symbol $($char$)$ and frequency pair.";

if $($args$.$length $!=1)$

$\{$

System.out.println$("$Invalid number of command line arguments"$)$;

System.out.println$($usage$)$;

System.exit$(1)$;

$\}$

$//$Complete the implementation of this method

$\}$

catch$($PQueueException e$)$

$\{$

System.out.println$($e$)$;

$\}$

$\}$

$\}$