diff --git a/src/12/c13/c13_avl.cpp b/src/12/c13/c13_avl.cpp
new file mode 100644
index 0000000..1527a19
--- /dev/null
+++ b/src/12/c13/c13_avl.cpp
@@ -0,0 +1,135 @@
+#include <iostream>
+#include <vector>
+#include <algorithm>
+
+using namespace std;
+
+struct Node {
+    int key;    // 节点的关键字
+    int left;   // 左子节点在数组中的索引
+    int right;  // 右子节点在数组中的索引
+    int height; // 节点高度
+
+    Node(int k = 0) : key(k), left(-1), right(-1), height(1) {}
+};
+
+class AVLTree {
+private:
+    vector<Node> tree; // 存储节点的数组
+    int root;          // 根节点的索引
+    int size;          // 当前节点数
+    const int MAX_SIZE = 100; // 最大节点数
+
+    // 获取节点高度
+    int getHeight(int index) {
+        if (index == -1) return 0;
+        return tree[index].height;
+    }
+
+    // 计算平衡因子
+    int getBalance(int index) {
+        if (index == -1) return 0;
+        return getHeight(tree[index].left) - getHeight(tree[index].right);
+    }
+
+    // 右旋
+    int rightRotate(int y) {
+        int x = tree[y].left;
+        int T2 = tree[x].right;
+
+        // 执行旋转
+        tree[x].right = y;
+        tree[y].left = T2;
+
+        // 更新高度
+        tree[y].height = max(getHeight(tree[y].left), getHeight(tree[y].right)) + 1;
+        tree[x].height = max(getHeight(tree[x].left), getHeight(tree[x].right)) + 1;
+
+        return x;
+    }
+
+    // 左旋
+    int leftRotate(int x) {
+        int y = tree[x].right;
+        int T2 = tree[y].left;
+
+        // 执行旋转
+        tree[y].left = x;
+        tree[x].right = T2;
+
+        // 更新高度
+        tree[x].height = max(getHeight(tree[x].left), getHeight(tree[x].right)) + 1;
+        tree[y].height = max(getHeight(tree[y].left), getHeight(tree[y].right)) + 1;
+
+        return y;
+    }
+
+    // 插入节点并返回新的根索引
+    int insertNode(int node, int key) {
+        // 1. 进行普通的 BST 插入
+        if (node == -1) {
+            if (size >= MAX_SIZE) {
+                cout << "Tree is full!" << endl;
+                return -1;
+            }
+            tree.emplace_back(Node(key));
+            return size++;
+        }
+
+        if (key < tree[node].key) {
+            tree[node].left = insertNode(tree[node].left, key);
+        }
+        else if (key > tree[node].key) {
+            tree[node].right = insertNode(tree[node].right, key);
+        }
+        else { // 相同的键不插入
+            return node;
+        }
+
+        // 2. 更新高度
+        tree[node].height = 1 + max(getHeight(tree[node].left), getHeight(tree[node].right));
+
+        // 3. 获取平衡因子
+        int balance = getBalance(node);
+
+        // 4. 如果不平衡，进行相应的旋转
+
+        // 左左情况
+        if (balance > 1 && key < tree[tree[node].left].key)
+            return rightRotate(node);
+
+        // 右右情况
+        if (balance < -1 && key > tree[tree[node].right].key)
+            return leftRotate(node);
+
+        // 左右情况
+
+        // 右左情况
+
+        return node; // 无需旋转
+    }
+
+    // 中序遍历
+    void inorderTraversal(int node) {
+        if (node == -1) return;
+        inorderTraversal(tree[node].left);
+        cout << tree[node].key << " ";
+        inorderTraversal(tree[node].right);
+    }
+
+public:
+    AVLTree() : root(-1), size(0) {
+        tree.reserve(MAX_SIZE);
+    }
+
+    // 插入键
+    void insert(int key) {
+        root = insertNode(root, key);
+    }
+
+    // 中序遍历打印
+    void inorder() {
+        inorderTraversal(root);
+        cout << endl;
+    }
+};