diff --git a/codes/cpp/chapter_hashing/hash_map.cpp b/codes/cpp/chapter_hashing/hash_map.cpp
index 1f295ec7b..090c2eb10 100644
--- a/codes/cpp/chapter_hashing/hash_map.cpp
+++ b/codes/cpp/chapter_hashing/hash_map.cpp
@@ -39,13 +39,13 @@ int main() {
     }
 
     cout << "\n单独遍历键 Key" << endl;
-    for (auto key : map) {
-        cout << key.first << endl;
+    for (auto kv : map) {
+        cout << kv.first << endl;
     }
 
     cout << "\n单独遍历值 Value" << endl;
-    for (auto val : map) {
-        cout << val.second << endl;
+    for (auto kv : map) {
+        cout << kv.second << endl;
     }
 
     return 0;
diff --git a/docs/chapter_hashing/hash_map.md b/docs/chapter_hashing/hash_map.md
index 6d10503bd..63ee3e347 100755
--- a/docs/chapter_hashing/hash_map.md
+++ b/docs/chapter_hashing/hash_map.md
@@ -299,12 +299,12 @@
         cout << kv.first << " -> " << kv.second << endl;
     }
     // 单独遍历键 key
-    for (auto key: map) {
-        cout << key.first << endl;
+    for (auto kv: map) {
+        cout << kv.first << endl;
     }
     // 单独遍历值 value
-    for (auto val: map) {
-        cout << val.second << endl;
+    for (auto kv: map) {
+        cout << kv.second << endl;
     }
     ```