public class Solution
extends Object
720 - Longest Word in Dictionary\.
Medium
Given an array of strings `words` representing an English Dictionary, return _the longest word in_ `words` _that can be built one character at a time by other words in_ `words`.
If there is more than one possible answer, return the longest word with the smallest lexicographical order. If there is no answer, return the empty string.
**Example 1:**
**Input:** words = ["w","wo","wor","worl","world"]
**Output:** "world"
**Explanation:** The word "world" can be built one character at a time by "w", "wo", "wor", and "worl".
**Example 2:**
**Input:** words = ["a","banana","app","appl","ap","apply","apple"]
**Output:** "apple"
**Explanation:** Both "apply" and "apple" can be built from other words in the dictionary. However, "apple" is lexicographically smaller than "apply".
**Constraints:**
* `1 <= words.length <= 1000`
* `1 <= words[i].length <= 30`
* `words[i]` consists of lowercase English letters.