Fs.java

/*
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import java.util.*;
import java.util.Map;
 
/**
 *
 * @author cteam92
 */
public class Fs {
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Map<String, String> toMorse = new HashMap<String, String>();
        Map<String, String> fromMorse = new HashMap<String, String>();
 
        toMorse.put("A", ".-");
        toMorse.put("B", "-...");
        toMorse.put("C", "-.-.");
        toMorse.put("D", "-..");
        toMorse.put("E", ".");
        toMorse.put("F", "..-.");
        toMorse.put("G", "--.");
        toMorse.put("H", "....");
        toMorse.put("I", "..");
        toMorse.put("J", ".---");
        toMorse.put("K", "-.-");
        toMorse.put("L", ".-..");
        toMorse.put("M", "--");
        toMorse.put("N", "-.");
        toMorse.put("O", "---");
        toMorse.put("P", ".--.");
        toMorse.put("Q", "--.-");
        toMorse.put("R", ".-.");
        toMorse.put("S", "...");
        toMorse.put("T", "-");
        toMorse.put("U", "..-");
        toMorse.put("V", "...-");
        toMorse.put("W", ".--");
        toMorse.put("X", "-..-");
        toMorse.put("Y", "-.--");
        toMorse.put("Z", "--..");
        toMorse.put("_", "..--");
        toMorse.put(",", ".-.-");
        toMorse.put(".", "---.");
        toMorse.put("?", "----");
 
        fromMorse.put(".-", "A");
        fromMorse.put("-...", "B");
        fromMorse.put("-.-.", "C");
        fromMorse.put("-..", "D");
        fromMorse.put(".", "E");
        fromMorse.put("..-.", "F");
        fromMorse.put("--.", "G");
        fromMorse.put("....", "H");
        fromMorse.put("..", "I");
        fromMorse.put(".---", "J");
        fromMorse.put("-.-", "K");
        fromMorse.put(".-..", "L");
        fromMorse.put("--", "M");
        fromMorse.put("-.", "N");
        fromMorse.put("---", "O");
        fromMorse.put(".--.", "P");
        fromMorse.put("--.-", "Q");
        fromMorse.put(".-.", "R");
        fromMorse.put("...", "S");
        fromMorse.put("-", "T");
        fromMorse.put("..-", "U");
        fromMorse.put("...-", "V");
        fromMorse.put(".--", "W");
        fromMorse.put("-..-", "X");
        fromMorse.put("-.--", "Y");
        fromMorse.put("--..", "Z");
        fromMorse.put("..--", "_");
        fromMorse.put(".-.-", ",");
        fromMorse.put("---.", ".");
        fromMorse.put("----", "?");
 
        Scanner sc = new Scanner(System.in);
        while (true) {
            if (!sc.hasNext()) break;
 
            // get numbers
            String input = sc.nextLine();
            String morseCode = "";
            String numbers = "";
            for (int i = 0; i < input.length(); i++) {
                String thisIndex = input.substring(i, i + 1);
                morseCode += toMorse.get(thisIndex);
                numbers = toMorse.get(thisIndex).length() + numbers;
            }
 
            // decode by reversed numbers
            int pointer = 0;
            for (int i = 0; i < numbers.length(); i++) {
                int thisLen = Integer.parseInt(numbers.substring(i, i + 1));
                String toDecode = morseCode.substring(pointer, pointer + thisLen);
                System.out.print(fromMorse.get(toDecode));
 
                pointer += thisLen;
            }
            System.out.println();
        }
    }
}