Given an array of strings words
, find the longest string in words
such that every prefix of it is also in words
.
- For example, let
words = ["a", "app", "ap"]
. The string"app"
has prefixes"ap"
and"a"
, all of which are inwords
.
Return the string described above. If there is more than one string with the same length, return the lexicographically smallest one, and if no string exists, return ""
.
Example 1:
Input: words = ["k","ki","kir","kira", "kiran"] Output: "kiran" Explanation: "kiran" has prefixes "kira", "kir", "ki", and "k", and all of them appear in words.
Example 2:
Input: words = ["a", "banana", "app", "appl", "ap", "apply", "apple"] Output: "apple" Explanation: Both "apple" and "apply" have all their prefixes in words. However, "apple" is lexicographically smaller, so we return that.
Example 3:
Input: words = ["abc", "bc", "ab", "qwe"] Output: ""
Constraints:
1 <= words.length <= 105
1 <= words[i].length <= 105
1 <= sum(words[i].length) <= 105