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"title": "Word Ladder II",
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"content": "<p>A <strong>transformation sequence</strong> from word <code>beginWord</code> to word <code>endWord</code> using a dictionary <code>wordList</code> is a sequence of words <code>beginWord -> s<sub>1</sub> -> s<sub>2</sub> -> ... -> s<sub>k</sub></code> such that:</p>\n\n<ul>\n\t<li>Every adjacent pair of words differs by a single letter.</li>\n\t<li>Every <code>s<sub>i</sub></code> for <code>1 <= i <= k</code> is in <code>wordList</code>. Note that <code>beginWord</code> does not need to be in <code>wordList</code>.</li>\n\t<li><code>s<sub>k</sub> == endWord</code></li>\n</ul>\n\n<p>Given two words, <code>beginWord</code> and <code>endWord</code>, and a dictionary <code>wordList</code>, return <em>all the <strong>shortest transformation sequences</strong> from</em> <code>beginWord</code> <em>to</em> <code>endWord</code><em>, or an empty list if no such sequence exists. Each sequence should be returned as a list of the words </em><code>[beginWord, s<sub>1</sub>, s<sub>2</sub>, ..., s<sub>k</sub>]</code>.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log","cog"]\n<strong>Output:</strong> [["hit","hot","dot","dog","cog"],["hit","hot","lot","log","cog"]]\n<strong>Explanation:</strong> There are 2 shortest transformation sequences:\n"hit" -> "hot" -> "dot" -> "dog" -> "cog"\n"hit" -> "hot" -> "lot" -> "log" -> "cog"\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log"]\n<strong>Output:</strong> []\n<strong>Explanation:</strong> The endWord "cog" is not in wordList, therefore there is no valid transformation sequence.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= beginWord.length <= 5</code></li>\n\t<li><code>endWord.length == beginWord.length</code></li>\n\t<li><code>1 <= wordList.length <= 1000</code></li>\n\t<li><code>wordList[i].length == beginWord.length</code></li>\n\t<li><code>beginWord</code>, <code>endWord</code>, and <code>wordList[i]</code> consist of lowercase English letters.</li>\n\t<li><code>beginWord != endWord</code></li>\n\t<li>All the words in <code>wordList</code> are <strong>unique</strong>.</li>\n</ul>\n",
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"code": "class Solution {\npublic:\n vector<vector<string>> findLadders(string beginWord, string endWord, vector<string>& wordList) {\n \n }\n};",
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"code": "class Solution {\n public List<List<String>> findLadders(String beginWord, String endWord, List<String> wordList) {\n \n }\n}",
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"code": "class Solution(object):\n def findLadders(self, beginWord, endWord, wordList):\n \"\"\"\n :type beginWord: str\n :type endWord: str\n :type wordList: List[str]\n :rtype: List[List[str]]\n \"\"\"\n ",
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"code": "class Solution:\n def findLadders(self, beginWord: str, endWord: str, wordList: List[str]) -> List[List[str]]:\n ",
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"code": "\n\n/**\n * Return an array of arrays of size *returnSize.\n * The sizes of the arrays are returned as *returnColumnSizes array.\n * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().\n */\nchar *** findLadders(char * beginWord, char * endWord, char ** wordList, int wordListSize, int* returnSize, int** returnColumnSizes){\n\n}",
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"code": "public class Solution {\n public IList<IList<string>> FindLadders(string beginWord, string endWord, IList<string> wordList) {\n \n }\n}",
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"code": "/**\n * @param {string} beginWord\n * @param {string} endWord\n * @param {string[]} wordList\n * @return {string[][]}\n */\nvar findLadders = function(beginWord, endWord, wordList) {\n \n};",
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"code": "# @param {String} begin_word\n# @param {String} end_word\n# @param {String[]} word_list\n# @return {String[][]}\ndef find_ladders(begin_word, end_word, word_list)\n \nend",
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"code": "class Solution {\n func findLadders(_ beginWord: String, _ endWord: String, _ wordList: [String]) -> [[String]] {\n \n }\n}",
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"code": "func findLadders(beginWord string, endWord string, wordList []string) [][]string {\n \n}",
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"code": "object Solution {\n def findLadders(beginWord: String, endWord: String, wordList: List[String]): List[List[String]] = {\n \n }\n}",
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"lang": "Kotlin",
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"code": "class Solution {\n fun findLadders(beginWord: String, endWord: String, wordList: List<String>): List<List<String>> {\n \n }\n}",
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"code": "impl Solution {\n pub fn find_ladders(begin_word: String, end_word: String, word_list: Vec<String>) -> Vec<Vec<String>> {\n \n }\n}",
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"lang": "PHP",
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"code": "class Solution {\n\n /**\n * @param String $beginWord\n * @param String $endWord\n * @param String[] $wordList\n * @return String[][]\n */\n function findLadders($beginWord, $endWord, $wordList) {\n \n }\n}",
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"code": "function findLadders(beginWord: string, endWord: string, wordList: string[]): string[][] {\n\n};",
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"code": "(define/contract (find-ladders beginWord endWord wordList)\n (-> string? string? (listof string?) (listof (listof string?)))\n\n )",
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"lang": "Erlang",
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"code": "-spec find_ladders(BeginWord :: unicode:unicode_binary(), EndWord :: unicode:unicode_binary(), WordList :: [unicode:unicode_binary()]) -> [[unicode:unicode_binary()]].\nfind_ladders(BeginWord, EndWord, WordList) ->\n .",
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"lang": "Elixir",
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"code": "defmodule Solution do\n @spec find_ladders(begin_word :: String.t, end_word :: String.t, word_list :: [String.t]) :: [[String.t]]\n def find_ladders(begin_word, end_word, word_list) do\n\n end\nend",
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"sampleTestCase": "\"hit\"\n\"cog\"\n[\"hot\",\"dot\",\"dog\",\"lot\",\"log\",\"cog\"]",
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For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu99 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. 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