SimplifyPath

Change-Id: I2cefaca9f3b954bf64b5a3262c4b52c8b8039f32

SimplifyPath.java

@@ -0,0 +1,46 @@
+/*
+ Author:     Andy, [email protected]
+ Date:       Jan 11, 2015
+ Problem:    Simplify Path
+ Difficulty: Easy
+ Source:     https://oj.leetcode.com/problems/simplify-path/
+ Notes:
+ Given an absolute path for a file (Unix-style), simplify it.
+
+ For example,
+ path = "/home/", => "/home"
+ path = "/a/./b/../../c/", => "/c"
+
+ Corner Cases:
+ Did you consider the case where path = "/../"?
+ In this case, you should return "/".
+ Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
+ In this case, you should ignore redundant slashes and return "/home/foo".
+
+ Solution: Add an additional '/' at the end of 'path' for simply detecting the end.
+ */
+public class Solution {
+    public String simplifyPath(String path) {
+        if(path.length()==0) return "/";
+        if(path.charAt(0)!='/') return "/";
+        ArrayList<String> dirs = new ArrayList<String>();
+        String[] str = path.split("/");
+        for (int i = 0; i < str.length; ++i) {
+            if ((i == 0 || i == str.length - 1) && str[i].compareTo("") == 0) continue;
+            if (str[i].compareTo("..") == 0) {
+                if (dirs.isEmpty() == false) {
+                    dirs.remove(dirs.size() - 1);
+                }
+            } else if ((str[i].compareTo(".") != 0) && (str[i].compareTo("") != 0)) {
+                dirs.add(str[i]);
+            }
+        }
+        if (dirs.isEmpty() == true) return "/";
+        StringBuilder res = new StringBuilder();
+        for (int i = 0; i < dirs.size(); ++i) {
+            res.append("/");
+            res.append(dirs.get(i));
+        }
+        return res.toString();
+    }
+}