71. 简化路径

Author: w2xi

README.md

@@ -33,6 +33,7 @@
 |66|[加一](https://leetcode-cn.com/problems/plus-one/)|[JavaScript](./algorithms/plus-one.js)|Easy|
 |69|[x 的平方根 ](https://leetcode.cn/problems/sqrtx/)|[JavaScript](./algorithms/sqrtx.js)|Easy|
 |70|[爬楼梯](https://leetcode.cn/problems/climbing-stairs/)|[JavaScript](./algorithms/climbing-stairs.js)|Easy|
+|71|[简化路径](https://leetcode.cn/problems/simplify-path/)|[JavaScript](./algorithms/simplify-path.js)|Medium|
 |73|[矩阵置零](https://leetcode.cn/problems/set-matrix-zeroes/)|[JavaScript](./algorithms/set-matrix-zeroes.js)|Medium|
 |82|[删除排序链表中的重复元素 II](https://leetcode.cn/problems/remove-duplicates-from-sorted-list-ii/)|[JavaScript](./algorithms/remove-duplicates-from-sorted-list-ii.js)|Medium|
 |83|[删除排序链表中的重复元素](https://leetcode.cn/problems/remove-duplicates-from-sorted-list/)|[JavaScript](./algorithms/remove-duplicates-from-sorted-list.js)|Easy|

algorithms/simplify-path.js

@@ -0,0 +1,21 @@
+/**
+ * @param {string} path
+ * @return {string}
+ */
+var simplifyPath = function (path) {
+  path = path.split("/");
+  let stack = [];
+
+  // 忽略 '.' ''
+  // 遇到 '..' 则弹出栈顶
+
+  for (let char of path) {
+    if (char === "..") {
+      stack.pop();
+    } else if (char && char !== ".") {
+      stack.push(char);
+    }
+  }
+
+  return `/${stack.join("/")}`;
+};