// Lib

class Haffman {
  Tree;
  public:
  Haffman() {
    init(Tree);
  }
  code(int size, type const* data) {
    std::vector<type> new
    for(i = 0; i < size; i++) {
      new.push(data[i].coded());
      Tree.add(data[i]);
    }
    return pair(new.size(), new.data());
  }
  decode(int size, type const* data) {
    std::vector<type> new
    for(i = 0; i < size; i++) {
      new.push(data[i].encoded());
      Tree.add(data[i]);
    }
    return pair(new.size(), new.data());
  }
};

// User_for_file

Haffman my_h();
while(!eof) {
 data = fread...
 fwrite(code(size,data));
}
close file

// User_for_console

Haffman my_h();
data = stdin;
stdout = code(size,data);

// User-console-program
  if from console user_for_console
    else user_for_file