diff --git "a/2101040022/chapter_9/P110 \345\271\263\350\241\241\344\272\214\345\217\211\346\240\221.cpp" "b/2101040022/chapter_9/P110 \345\271\263\350\241\241\344\272\214\345\217\211\346\240\221.cpp"
new file mode 100644
index 0000000000000000000000000000000000000000..3e19e5e9c124501cfd293e05a5cabea2806190b2
--- /dev/null
+++ "b/2101040022/chapter_9/P110 \345\271\263\350\241\241\344\272\214\345\217\211\346\240\221.cpp"	
@@ -0,0 +1,28 @@
+class Solution {
+  public:
+    bool isBalanced(TreeNode* root) {
+        if (getdepth(root) != -1) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+    int getdepth(TreeNode* node) {
+        if (node == NULL) {
+            return 0;
+        }
+        int leftlength = getdepth(node->left);
+        int rightlength = getdepth(node->right);
+        if (leftlength == -1) {
+            return -1;
+        }
+        if (rightlength == -1) {
+            return -1;
+        }
+        if (abs(leftlength - rightlength) > 1) {
+            return -1;
+        } else {
+            return max(leftlength, rightlength) + 1;
+        }
+    }
+};
\ No newline at end of file