update description of 71_SimplifyPath

Author: Binlogo

71_SimplifyPath.swift

@@ -0,0 +1,40 @@
+//
+// 71. 简化路径
+//
+// 题目链接：https://leetcode-cn.com/problems/simplify-path/
+// 标签：栈、字符串
+// 要点：根据题意，考虑清楚出入栈条件，以及跳过逻辑
+// 时间复杂度：O(N)
+// 空间复杂度：O(N)
+//
+
+import Foundation
+
+class Solution {
+    func simplifyPath(_ path: String) -> String {
+        let paths = path.split(separator: "/")
+        
+        var pathStack = [String]()
+        
+        for path in paths {
+            guard path != ".", !path.isEmpty else { continue }
+            
+            if path == ".." {
+                pathStack.popLast()
+            } else {
+                pathStack.append(String(path))
+            }
+        }
+        
+        return "/" + pathStack.joined(separator: "/")
+    }
+}
+
+// Tests
+let s = Solution()
+s.simplifyPath("/home/") == "/home"
+s.simplifyPath("/../") == "/"
+s.simplifyPath("/home//foo/") == "/home/foo"
+s.simplifyPath("/a/./b/../../c/") == "/c"
+s.simplifyPath("/a/../../b/../c//.//") == "/c"
+s.simplifyPath("/a//b////c/d//././/..") == "/a/b/c"

LeetCodePlayground.playground/Pages/71_SimplifyPath.xcplaygroundpage/Contents.swift

@@ -1,5 +1,15 @@
 //: [Previous](@previous)
 
+//
+// 71. 简化路径
+//
+// 题目链接：https://leetcode-cn.com/problems/simplify-path/
+// 标签：栈、字符串
+// 要点：根据题意，考虑清楚出入栈条件，以及跳过逻辑
+// 时间复杂度：O(N)
+// 空间复杂度：O(N)
+//
+
 import Foundation
 
 class Solution {

README.md

@@ -54,9 +54,10 @@ LeetCode 💖 Swift，攻克[数据结构](#数据结构)与[算法](#算法)。
 
 ### 栈
 
-|                             标题                             |     标签      | 描述                           |                            题解                            |
-| :----------------------------------------------------------: | :-----------: | ------------------------------ | :--------------------------------------------------------: |
-| 1003. [检查替换后的词是否有效](https://leetcode-cn.com/problems/check-if-word-is-valid-after-substitutions/) | `字符串` `栈` | 按给定规则检查替换后的词有效性 | [Swift](./1003_CheckIfWordIsValidAfterSubstitutions.swift) |
+|                             标题                             |     标签      | 描述                                                         |                            题解                            |
+| :----------------------------------------------------------: | :-----------: | ------------------------------------------------------------ | :--------------------------------------------------------: |
+| 1003. [检查替换后的词是否有效](https://leetcode-cn.com/problems/check-if-word-is-valid-after-substitutions/) | `字符串` `栈` | 按给定规则检查替换后的词有效性                               | [Swift](./1003_CheckIfWordIsValidAfterSubstitutions.swift) |
+| [71. 简化路径](https://leetcode-cn.com/problems/simplify-path/) | `字符串` `栈` | 以 Unix 风格给出一个文件的**绝对路径**，你需要简化它。或者换句话说，将其转换为规范路径。 |              [Swift](./71_SimplifyPath.swift)              |
 
 ### 队列