def search(key)
      base = @base
      chck = @chck
      node = @base[0]
      kin = KeyStream.new(key)
    
      while true
        code = kin.read
        idx = node + code
        node = base[idx]
      
        if(chck[idx] == code)
          if(node >= 0)
            next
          elsif(kin.eos? or key_exists?(kin, node))
            return Node::Base.ids(node)
          end
          return -1
        end
      end
    end
def search(key)
      base = @base
      chck = @chck
      node = @base[0]
      kin = KeyStream.new(key)
    
      while true
        code = kin.read
        idx = node + code
        node = base[idx]
      
        if(chck[idx] == code)
          if(node >= 0)
            next
          elsif(kin.eos? or key_exists?(kin, node))
            return Node::Base.ids(node)
          end
          return -1
        end
      end
    end
キーを検索する
key:: 検索対象のキー文字列
return:: キーが見つかった場合はそのIDを、見つからなかった場合は-1を返す