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在查找序列的子序列方面，search() 算法和 find_end() 算法相似，但它所查找的是第一个匹配项而不是最后一个。

和 find_end() 算法一样，它也有两个版本，第二个版本接受用来比较元素的谓词作为第 5 个参数。可以用 search() 来验证前面使用 find_end() 搜索的结果。 如何改变每次遍历搜索的具体范围是它们的主要不同之处。下面是一个示例：

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string text {"Smith, where Jones had had \"had\", had had \"had had\"."" \"Had had\" had had the examiners\' approval."}; std::cout << text << std::endl; string phrase {"had had"}; size_t count {}; auto iter = std::begin(text); auto end_iter = end(text); while((iter = std::search(iter, end_iter, std::begin(phrase), std::end (phrase) , [](char ch1, char ch2) { return std::toupper (ch1) == std:: toupper (ch2); })) != end_iter) {     ++count;     std::advance(iter, phrase.size()); // Move to beyond end of subsequence found } std::cout << "\n\""<< phrase << "\" was found "<< count << " times." << std::endl;

这段代码执行后会输出下面的内容：

Smith, where Jones had had "had", had had "had had". "Had had" had had the examiners' approval.
"had had" was found 5 times.

我们仍然忽略大小写来搜索“had had”，但会正向查找第一个匹配项。search() 算法返回的迭代器指向找到的子序列的第一个元素，因此为了搜索 phrase 的第二个实例，iter 必须增加 phrase 中元素的个数，使它指向下一个找到的序列的第一个元素。