Class Solution
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- All Implemented Interfaces:
public final class Solution3292 - Minimum Number of Valid Strings to Form Target II\.
Hard
You are given an array of strings
wordsand a stringtarget.A string
xis called valid ifxis a prefix of any string inwords.Return the minimum number of valid strings that can be concatenated to form
target. If it is not possible to formtarget, return-1.A prefix of a string is a substring that starts from the beginning of the string and extends to any point within it.
Example 1:
Input: words = "abc","aaaaa","bcdef", target = "aabcdabc"
Output: 3
Explanation:
The target string can be formed by concatenating:
Prefix of length 2 of
words[1], i.e."aa".Prefix of length 3 of
words[2], i.e."bcd".Prefix of length 3 of
words[0], i.e."abc".
Example 2:
Input: words = "abababab","ab", target = "ababaababa"
Output: 2
Explanation:
The target string can be formed by concatenating:
Prefix of length 5 of
words[0], i.e."ababa".Prefix of length 5 of
words[0], i.e."ababa".
Example 3:
Input: words = "abcdef", target = "xyz"
Output: \-1
Constraints:
1 <= words.length <= 100<code>1 <= wordsi.length <= 5 * 10<sup>4</sup></code>
The input is generated such that <code>sum(wordsi.length) <= 10<sup>5</sup></code>.
words[i]consists only of lowercase English letters.<code>1 <= target.length <= 5 * 10<sup>4</sup></code>
targetconsists only of lowercase English letters.