36 lines
772 B
Markdown
36 lines
772 B
Markdown
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# HashMap::Size / Empty
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```cpp
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size_t Size() const;
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bool Empty() const;
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```
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获取哈希表的元素数量或判断是否为空。
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**参数：** 无
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**返回：**
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- `Size()` - 返回元素数量
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- `Empty()` - 容器为空返回 `true`，否则返回 `false`
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**复杂度：** O(1)
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**示例：**
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```cpp
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XCEngine::Containers::HashMap<int, const char*> map;
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std::cout << "Empty: " << (map.Empty() ? "yes" : "no") << std::endl; // 输出 "yes"
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std::cout << "Size: " << map.Size() << std::endl; // 输出 0
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map.Insert(1, "one");
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map.Insert(2, "two");
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std::cout << "Empty: " << (map.Empty() ? "yes" : "no") << std::endl; // 输出 "no"
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std::cout << "Size: " << map.Size() << std::endl; // 输出 2
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```
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## 相关文档
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- [HashMap 总览](hashmap.md) - 返回类总览
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