一.什么是标签?
我们之前获取的源数据都是html数据,在一个html中我们看到
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
2 <html>
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5 <title>Chapter 15. Boost.Heap</title>
6 <link rel="stylesheet" href="../../doc/src/boostbook.css" type="text/css">
7 <meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
8 <link rel="home" href="index.html" title="The Boost C++ Libraries BoostBook Documentation Subset">
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