/**
 * Compress.  Using huffman table in args[0] compress the file in args[1] 
 * into the file in args[2]
 * 
 * @author rpj 
 * @version 22xi08
 */
import java.util.*;
import java.io.*;

public class Compress
{

    /**
     * main
     * read the file whose name is provided on commandline
     */
    public static void main (String[] args) {
        Scanner scan = null;
        try {
            scan = new Scanner(new File(args[0]));
        }
        catch (Exception fnfe) {
            System.err.println("Usage: java Compress tablefile tocompressfile compressedfile");
            System.exit(-1);
        }
        String cs; 
        // Read the huffman code table into a HashMap for easy encoding
        HashMap<Character, String> huffmanTable = new HashMap<Character, String>();
        while (scan.hasNextLine()) {
            cs = scan.nextLine();
            // each line in a huffman table begins with the character
            // followed by " : "
            // and then the 0-1 encoding
            // charAt(0) gives the character, and substring(4) gives the code
            huffmanTable.put(cs.charAt(0), cs.substring(4));
        }
        try {
            scan = new Scanner(new File(args[1]));
        }
        catch (Exception fnfe) {
            // handle this oops!
        }
        PrintStream outFile = null;
        try {
            outFile = new PrintStream(new File (args[2]));
        }
        catch (Exception e) {
            // handle this oops!
        }
        while (scan.hasNextLine()) {
            // one line at a time
            cs = scan.nextLine();
            // output the 0-1 code got by looking up each char in turn:
            for (int i = 0; i<cs.length(); i++) {
                outFile.print(huffmanTable.get(cs.charAt(i)));
            }
        }
        outFile.close();
    }
}