<code id='DE134ACE80'></code><style id='DE134ACE80'></style>
    • <acronym id='DE134ACE80'></acronym>
      <center id='DE134ACE80'><center id='DE134ACE80'><tfoot id='DE134ACE80'></tfoot></center><abbr id='DE134ACE80'><dir id='DE134ACE80'><tfoot id='DE134ACE80'></tfoot><noframes id='DE134ACE80'>

    • <optgroup id='DE134ACE80'><strike id='DE134ACE80'><sup id='DE134ACE80'></sup></strike><code id='DE134ACE80'></code></optgroup>
        1. <b id='DE134ACE80'><label id='DE134ACE80'><select id='DE134ACE80'><dt id='DE134ACE80'><span id='DE134ACE80'></span></dt></select></label></b><u id='DE134ACE80'></u>
          <i id='DE134ACE80'><strike id='DE134ACE80'><tt id='DE134ACE80'><pre id='DE134ACE80'></pre></tt></strike></i>

          刺问鼎娱乐客破解版pg赏金女王

          搜索引擎的工作原理(二)

          网页搜集是搜索引擎三段式工作的第一阶段的工作,在这个阶段搜索引擎完成原始网页的搜集,这些网页将作为下一个阶段的数据基础。那么搜索引擎在这个阶段会碰上哪些问题呢?网页搜集时机第一个问题就是,搜索引擎是什...