题目内容
URL normalization is useful for crawlers to avoid crawling the same resource more than once.
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There is no space in URL.
A path-ascending crawler would normally ascend to every path in each URL that it intends to crawl.
For example, when given a seed URL of ****.org/a/b/page. , it will attempt to crawl//a/, /b/, and/.
The Web has a very dynamic nature, meaning it can be created, updated and deleted at any moment.
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