Crawlers can prevent some engines from harvesting email addresses.
查看答案
The seed URLs are the crawl frontier.
A. 对
B. 错
The crawl frontier includes the seed URLs and all their hyperlinks.
A. 对
B. 错
URLs from the frontier need visiting only once.
A. 对
B. 错
To prioritize its downloads means to determine the order according to their relative importance.
A. 对
B. 错
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