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import java.util.Hashtable;
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public class LZW
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{
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int count;
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LZW()
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{
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inputDict = new Hashtable();
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outputDict = new Hashtable();
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w = new StringBuffer("");
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v = new StringBuffer("");
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count = 0;
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}
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/**/
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public int Encode(char k) // throws DoNotSend
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{
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int temp;
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String s = "" + w + k;
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if (inputDict.containsKey(s))
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{
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w = w.append(k);
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// throw new DoNotSend();
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return -1;
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/*
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Integer grrr = (Integer) inputDict.put(s,s);
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inputDict.put(grrr,s);
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return grrr.intValue();
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*/
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} else
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{
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Integer val = new Integer(count);
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inputDict.put(s, val);
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outputDict.put(val, s);
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w = new StringBuffer("" + k);
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return count++;
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/*
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Integer K = (Integer)inputDict.get("" + w);
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temp = K.intValue();
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return temp;
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*/
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}
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}
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public String Decode(int k)
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{
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Integer K = new Integer(k);
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return (String)outputDict.get(K);
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/*
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String entry;
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if (v.length() == 0)
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{
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v = new StringBuffer((String)outputDict.get(new Integer(k)));
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return (v.toString());
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} else
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{
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entry = new String((String)outputDict.get(K));
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if (entry.length() == 0)
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{ // remove this conditional to cause LZW bug
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entry = new String(v.toString() + v.charAt(0));
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}
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outputDict.put(K, "" + v + entry.charAt(0));
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v = new StringBuffer(entry);
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return entry;
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}
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*/
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}
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Hashtable inputDict;
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Hashtable outputDict;
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StringBuffer w;
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StringBuffer v;
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}
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class DoNotSend extends Exception
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{
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}
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