71.简化路径

题目描述

题解

栈

使用栈来记录字符串中出现的有效目录, 如果遇到.., 就将栈顶的目录弹出

public String simplifyPath(String path) {
    String[] strs = path.split("/");
    Deque<String> stack = new ArrayDeque<>();

    for (String str : strs) {
        if (str.equals("..")) {
            if (!stack.isEmpty()) {
                stack.pop();
            }
        }else if (!str.equals("") && !str.equals(".")) {
            stack.push(str);
        }
    }

    if (stack.isEmpty()) {
        return "/";
    } else {
        StringBuilder stringBuilder = new StringBuilder();
        while (!stack.isEmpty()){
            stringBuilder.append("/").append(stack.pollLast());
        }
        return stringBuilder.toString();
    }
}