diff --git a/problems/0242.有效的字母异位词.md b/problems/0242.有效的字母异位词.md
index 10939b0f..8aa0d171 100644
--- a/problems/0242.有效的字母异位词.md
+++ b/problems/0242.有效的字母异位词.md
@@ -140,6 +140,23 @@ func isAnagram(s string, t string) bool {
 }
 ```
 
+javaScript:
+
+```js
+var isAnagram = function(s, t) {
+    const resSet = new Array(25).fill(0);
+    const base = "a".charCodeAt();
+    for(const i of s) {
+        resSet[i.charCodeAt() - base]++;
+    }
+    for(const i of t) {
+        resSet[i.charCodeAt() - base]--;
+        // if(val < 0) return false; 
+    }
+    return resSet.every(i => !i);
+};
+```
+
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