unordered_set.find
时间: 2023-08-26 10:16:59 浏览: 184
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unordered_set.find()函数是用于在unordered_set容器中搜索指定元素的C++ STL内置函数。它返回一个迭代器,指向找到的元素。如果找不到指定元素,则返回指向unordered_set的end()迭代器。该函数的时间复杂度是平均O(1)。下面是一个示例代码,展示了如何使用unordered_set.find()函数来搜索元素并判断是否存在:
```cpp
#include <iostream>
#include <unordered_set>
#include <string>
using namespace std;
int main() {
unordered_set<string> sampleSet = { "geeks1", "for", "geeks2" };
if (sampleSet.find("geeks1") != sampleSet.end()) {
cout << "element found." << endl;
} else {
cout << "element not found." << endl;
}
return 0;
}
```
在这个示例中,我们创建了一个包含三个字符串的unordered_set(sampleSet)。然后,我们使用find()函数来搜索"geeks1"这个元素。如果找到了,就输出"element found.",否则输出"element not found."。<span class="em">1</span><span class="em">2</span><span class="em">3</span>
#### 引用[.reference_title]
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