{ "data": { "question": { "questionId": "3557", "questionFrontendId": "3292", "boundTopicId": null, "title": "Minimum Number of Valid Strings to Form Target II", "titleSlug": "minimum-number-of-valid-strings-to-form-target-ii", "content": "

You are given an array of strings words and a string target.

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A string x is called valid if x is a prefix of any string in words.

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Return the minimum number of valid strings that can be concatenated to form target. If it is not possible to form target, return -1.

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Example 1:

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Input: words = ["abc","aaaaa","bcdef"], target = "aabcdabc"

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Output: 3

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Explanation:

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The target string can be formed by concatenating:

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Example 2:

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Input: words = ["abababab","ab"], target = "ababaababa"

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Output: 2

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Explanation:

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The target string can be formed by concatenating:

\n\n\n
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Example 3:

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Input: words = ["abcdef"], target = "xyz"

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Output: -1

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Constraints:

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exact-integer?)\n )", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "-spec min_valid_strings(Words :: [unicode:unicode_binary()], Target :: unicode:unicode_binary()) -> integer().\nmin_valid_strings(Words, Target) ->\n .", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "defmodule Solution do\n @spec min_valid_strings(words :: [String.t], target :: String.t) :: integer\n def min_valid_strings(words, target) do\n \n end\nend", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"2.3K\", \"totalSubmission\": \"16.5K\", \"totalAcceptedRaw\": 2280, \"totalSubmissionRaw\": 16482, \"acRate\": \"13.8%\"}", "hints": [ "Let dp[i] be the minimum cost to form the prefix of length i of target.", "Use Rabin-Karp to hash every prefix and store it in a HashSet.", "Use Binary search to find the longest substring starting at index i (target[i..j]) that has a hash present in the HashSet.", "Inverse Modulo precomputation can optimise hash calculation.", "Use Lazy Segment Tree, or basic Segment Tree to update dp[i..j].", "Is it possible to use two TreeSets to update dp[i..j]?" ], "solution": null, "status": null, "sampleTestCase": "[\"abc\",\"aaaaa\",\"bcdef\"]\n\"aabcdabc\"", "metaData": "{\n \"name\": \"minValidStrings\",\n \"params\": [\n {\n \"name\": \"words\",\n \"type\": \"string[]\"\n },\n {\n \"type\": \"string\",\n \"name\": \"target\"\n }\n ],\n \"return\": {\n \"type\": \"integer\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 21. Using compile arguments: --enable-preview --release 21

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Python 2.7.12.

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C# 12 with .NET 8 runtime

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Node.js 20.10.0.

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Ruby 3.2

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Go 1.23

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Python 3.11.

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Kotlin 1.9.0.

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TypeScript 5.1.6, Node.js 20.10.0.

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Racket CS v8.11

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