1002. 查找共用字符

Author: w2xi

README.md

@@ -134,5 +134,6 @@
 |965|[单值二叉树](https://leetcode.cn/problems/univalued-binary-tree/)|[JavaScript](./algorithms/univalued-binary-tree.js)|Easy|
 |977|[有序数组的平方](https://leetcode.cn/problems/squares-of-a-sorted-array/)|[JavaScript](./algorithms/squares-of-a-sorted-array.js)|Easy|
 |988|[从叶结点开始的最小字符串](https://leetcode.cn/problems/smallest-string-starting-from-leaf/)|[JavaScript](./algorithms/smallest-string-starting-from-leaf.js)|Medium|
+|1002|[查找共用字符](https://leetcode.cn/problems/find-common-characters/)|[JavaScript](./algorithms/find-common-characters.js)|Easy|
 |面试题 04.12|[面试题 04.12. 求和路径](https://leetcode.cn/problems/paths-with-sum-lcci/)|[JavaScript](./algorithms/paths-with-sum-lcci.js)|Medium|
 |面试题 02.07|[面试题 02.07. 链表相交](https://leetcode.cn/problems/intersection-of-two-linked-lists-lcci/)|[JavaScript](./algorithms/intersection-of-two-linked-lists-lcci.js)|Easy|

algorithms/find-common-characters.js

@@ -0,0 +1,37 @@
+/**
+ * @param {string[]} words
+ * @return {string[]}
+ */
+var commonChars = function (words) {
+  // 数组哈希计数
+  const result = [];
+  const size = 26;
+  const firstHash = Array(size).fill(0);
+  const firstWord = words[0];
+
+  for (let i = 0; i < firstWord.length; i++) {
+    const index = firstWord[i].charCodeAt() - "a".charCodeAt();
+    firstHash[index]++;
+  }
+  const tempHash = Array(26).fill(0);
+  for (let i = 1; i < words.length; i++) {
+    const curr = words[i];
+    for (let j = 0; j < curr.length; j++) {
+      const index = curr[j].charCodeAt() - "a".charCodeAt();
+      tempHash[index]++;
+    }
+    for (let k = 0; k < size; k++) {
+      firstHash[k] = Math.min(firstHash[k], tempHash[k]);
+    }
+    // reset
+    tempHash.fill(0);
+  }
+
+  for (let i = 0; i < firstHash.length; i++) {
+    while (firstHash[i]--) {
+      result.push(String.fromCharCode(i + "a".charCodeAt()));
+    }
+  }
+
+  return result;
+};