- Difficulty: Medium
- Tags: LeetCode, Medium, Trie, Array, Hash Table, String, leetcode-820, O(n), O(t)
Problem
A valid encoding of an array of words
is any reference string s
and array of indices indices
such that:
words.length == indices.length
- The reference string
s
ends with the'#'
character. - For each index
indices[i]
, the substring ofs
starting fromindices[i]
and up to (but not including) the next'#'
character is equal towords[i]
.
Given an array of words
, return the length of the shortest reference string s
possible of any valid encoding of words
.
Example 1:
Input: words = ["time", "me", "bell"]
Output: 10
Explanation: A valid encoding would be s = "time#bell#" and indices = [0, 2, 5
].
words[0] = "time", the substring of s starting from indices[0] = 0 to the next '#' is underlined in "time#bell#"
words[1] = "me", the substring of s starting from indices[1] = 2 to the next '#' is underlined in "time#bell#"
words[2] = "bell", the substring of s starting from indices[2] = 5 to the next '#' is underlined in "time#bell#"
Example 2:
Input: words = ["t"] Output: 2 Explanation: A valid encoding would be s = "t#" and indices = [0].
Constraints:
1 <= words.length <= 2000
1 <= words[i].length <= 7
words[i]
consists of only lowercase letters.