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docs/api/containers/hashmap/size.md

@@ -0,0 +1,35 @@
+# HashMap::Size / Empty
+
+```cpp
+size_t Size() const;
+bool Empty() const;
+```
+
+获取哈希表的元素数量或判断是否为空。
+
+**参数：** 无
+
+**返回：**
+- `Size()` - 返回元素数量
+- `Empty()` - 容器为空返回 `true`，否则返回 `false`
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+XCEngine::Containers::HashMap<int, const char*> map;
+
+std::cout << "Empty: " << (map.Empty() ? "yes" : "no") << std::endl; // 输出 "yes"
+std::cout << "Size: " << map.Size() << std::endl; // 输出 0
+
+map.Insert(1, "one");
+map.Insert(2, "two");
+
+std::cout << "Empty: " << (map.Empty() ? "yes" : "no") << std::endl; // 输出 "no"
+std::cout << "Size: " << map.Size() << std::endl; // 输出 2
+```
+
+## 相关文档
+
+- [HashMap 总览](hashmap.md) - 返回类总览