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import java.io.*;


public class LispInputStream {
  Reader reader;
  StreamTokenizer st;
  public LispInputStream(Reader reader){
    this.reader=reader;
    st=new StreamTokenizer(reader);
    st.resetSyntax();
    st.whitespaceChars('\u0000',' ');
    st.wordChars('!','\u00ff');
    st.ordinaryChar('\'');
    st.ordinaryChar('(');
    st.ordinaryChar(')');
    st.quoteChar('\"');
  }
  public int nextToken() throws IOException{
    int token=st.nextToken();
    switch(token){
    case StreamTokenizer.TT_NUMBER: 
      // System.out.println("Number: "+st.nval+"String:"+st.sval);
      break;
    case StreamTokenizer.TT_WORD: 
      // System.out.println("WORD: "+st.sval);
      break;
    default:
      // System.out.println("CHARACTER: "+token);
      break;
    }
    return token;
  }
  public LispObject readList() throws IOException{
    LispObject a=nextObject();
    int token=nextToken();
    if(token==')') return new Cons(a,Symbol.nil);
    else if(token=='.') return new Cons(a,nextObject());
    else{
      st.pushBack();
      return new Cons(a,readList());
    }
  }
  public LispObject nextObject() throws IOException{
    // System.out.println("nextObject");
    int token=nextToken();
    // System.out.println("token="+token);
    switch(token){
    case '(': {
      // System.out.println("readList");
      return readList();
    }
    case '\'': {
      // System.out.println("quote");
      LispObject ret=nextObject();
      return new Cons(Symbol.quote,new Cons(ret,Symbol.nil));
    }
    case '"': {
      return new LispString(st.sval);
    }
    case StreamTokenizer.TT_EOF: return null;
    case StreamTokenizer.TT_WORD: {
      if(Fixnum.isFixnumString(st.sval)) return new Fixnum(st.sval);
      if(Flonum.isFlonumString(st.sval)) return new Flonum(st.sval);
      return new Symbol(st.sval);
    }
    default:
      System.out.println("token="+token);
    }
    return null;
  }
  public static void main(String args[]) throws IOException{
    LispInputStream lis;
    if(args.length>0)
      lis=new LispInputStream(new FileReader(args[0]));
    else 
      lis=new LispInputStream(new InputStreamReader(System.in));
    LispObject lo=null;
    while((lo=lis.nextObject())!=null){
      System.out.println(lo);
    }
  }
}