0071.simplify-path.md

0071.Simplify-Path

Description

Given an absolute path for a file (Unix-style), simplify it. Or in other words, convert it to the canonical path.

In a UNIX-style file system, a period . refers to the current directory. Furthermore, a double period .. moves the directory up a level. For more information, see: Absolute path vs relative path in Linux/Unix

Note that the returned canonical path must always begin with a slash /, and there must be only a single slash / between two directory names. The last directory name (if it exists) must not end with a trailing /. Also, the canonical path must be the shortest string representing the absolute path. Example 1:

Input: "/home/"
Output: "/home"
Explanation: Note that there is no trailing slash after the last directory name.

Example 2:

Input: "/../"
Output: "/"
Explanation: Going one level up from the root directory is a no-op, as the root level is the highest level you can go.

Example 3:

Input: "/home//foo/"
Output: "/home/foo"
Explanation: In the canonical path, multiple consecutive slashes are replaced by a single one.

Example 4:

Input: "/a/./b/../../c/"
Output: "/c"

Example 5:

Input: "/a/../../b/../c//.//"
Output: "/c"

Example 5:

Input: "/a//b////c/d//././/.."
Output: "/a/b/c"

Tags: Math, String

题意

大概意思就是讲输入的绝对路径简化

题解

思路1

利用golang自带的函数解决。 注意：此方法会根据平台变换 【/】【\】

func simplifyPath(path string) string {
    return filepath.Clean(path)
}

思路2

func simplifyPath(path string) string {
    var stack []string
    for _, component := range strings.Split(path, "/") {
        if component == "" || component == "." {
            continue
        }
        if component == ".." {
            if len(stack) > 0 {
                stack = stack[:len(stack)-1]
            }
        } else {
            stack = append(stack, component)
        }
    }
    return "/" + strings.Join(stack, "/")
}

结语

如果你同我一样热爱数据结构、算法、LeetCode，可以关注我 GitHub 上的 LeetCode 题解：awesome-golang-algorithm