LeetCode: Simplify Path

改了很多次，这种麻烦的题目就是考你有没有考虑到所有情况

class Solution {
public:
    string simplifyPath(string path) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<string> S;
        string tmp = "";
        for (int i = 0; i < path.size(); i++) {
            if (path[i] == '/') {
                if (!tmp.size()) continue;
                else {
                    if (tmp == "..") {
                        if (S.size()) S.pop_back();
                    }
                    else if (tmp != ".") S.push_back(tmp);
                    tmp = "";
                }
            }
            else tmp = tmp + path[i];
        }
        if (tmp.size()) {
            if (tmp == ".") ;
            else if (tmp == "..") {
                if (S.size()) S.pop_back();
            }
            else S.push_back(tmp);
        }
        string ret = "";
        for (int i = 0; i < S.size(); i++) {
            ret = ret + "/" + S[i];
        }
        if (!ret.size()) return "/";
        return ret;
    }
};

 C#

public class Solution {
    public string SimplifyPath(string path) {
        Stack<string> S = new Stack<string>();
        string tmp = "";
        for (int i = 0; i < path.Length; i++) {
            if (path[i] == '/') {
                if (tmp.Length == 0) continue;
                else {
                    if (tmp == "..") {
                        if (S.Count > 0) S.Pop();
                    }
                    else if (tmp != ".") S.Push(tmp);
                    tmp = "";
                }
            }
            else tmp += path[i];
        }
        if (tmp.Length > 0) {
            if (tmp == ".") ;
            else if (tmp == "..") {
                if (S.Count > 0) S.Pop();
            }
            else S.Push(tmp);
        }
        string ans = "";
        while (S.Count > 0) {
            ans = S.Peek() + "/" + ans;
            S.Pop();
        }
        if (ans.Length == 0) return "/";
        ans = "/" + ans;
        return ans.Substring(0, ans.Length - 1);
    }
}