diff --git a/problems/1002.查找常用字符.md b/problems/1002.查找常用字符.md
index fd188660..9ec3c6c4 100644
--- a/problems/1002.查找常用字符.md
+++ b/problems/1002.查找常用字符.md
@@ -252,6 +252,36 @@ var commonChars = function (words) {
 	}
 	return res
 };
+
+// 方法二：map()
+var commonChars = function(words) {
+  let min_count = new Map()
+  // 统计字符串中字符出现的最小频率,以第一个字符串初始化
+  for(let str of words[0]) {
+    min_count.set(str, ((min_count.get(str) || 0) + 1))
+  }
+  // 从第二个单词开始统计字符出现次数
+  for(let i = 1; i < words.length; i++) {
+    let char_count = new Map()
+    for(let str of words[i]) { // 遍历字母
+      char_count.set(str, (char_count.get(str) || 0) + 1)
+    }
+    // 比较出最小的字符次数
+    for(let value of min_count) { // 注意这里遍历min_count!而不是单词
+      min_count.set(value[0], Math.min((min_count.get(value[0]) || 0), (char_count.get(value[0]) || 0)))
+    }
+  }
+  // 遍历map
+  let res = []
+  min_count.forEach((value, key) => {
+    if(value) {
+      for(let i=0; i<value; i++) {
+        res.push(key)
+      }
+    }
+  })
+  return res
+}
 ```
 
 TypeScript