mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
synced 2025-01-10 18:48:13 +08:00
188 lines
21 KiB
JSON
188 lines
21 KiB
JSON
{
|
|
"data": {
|
|
"question": {
|
|
"questionId": "3233",
|
|
"questionFrontendId": "3003",
|
|
"boundTopicId": null,
|
|
"title": "Maximize the Number of Partitions After Operations",
|
|
"titleSlug": "maximize-the-number-of-partitions-after-operations",
|
|
"content": "<p>You are given a <strong>0-indexed</strong> string <code>s</code> and an integer <code>k</code>.</p>\n\n<p>You are to perform the following partitioning operations until <code>s</code> is <strong>empty</strong>:</p>\n\n<ul>\n\t<li>Choose the <strong>longest</strong> <strong>prefix</strong> of <code>s</code> containing at most <code>k</code> <strong>distinct</strong> characters.</li>\n\t<li><strong>Delete</strong> the prefix from <code>s</code> and increase the number of partitions by one. The remaining characters (if any) in <code>s</code> maintain their initial order.</li>\n</ul>\n\n<p><strong>Before</strong> the operations, you are allowed to change <strong>at most</strong> <strong>one</strong> index in <code>s</code> to another lowercase English letter.</p>\n\n<p>Return <em>an integer denoting the <strong>maximum</strong> number of resulting partitions after the operations by optimally choosing at most one index to change.</em></p>\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> s = "accca", k = 2\n<strong>Output:</strong> 3\n<strong>Explanation: </strong>In this example, to maximize the number of resulting partitions, s[2] can be changed to 'b'.\ns becomes "acbca".\nThe operations can now be performed as follows until s becomes empty:\n- Choose the longest prefix containing at most 2 distinct characters, "<u>ac</u>bca".\n- Delete the prefix, and s becomes "bca". The number of partitions is now 1.\n- Choose the longest prefix containing at most 2 distinct characters, "<u>bc</u>a".\n- Delete the prefix, and s becomes "a". The number of partitions is now 2.\n- Choose the longest prefix containing at most 2 distinct characters, "<u>a</u>".\n- Delete the prefix, and s becomes empty. The number of partitions is now 3.\nHence, the answer is 3.\nIt can be shown that it is not possible to obtain more than 3 partitions.</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> s = "aabaab", k = 3\n<strong>Output:</strong> 1\n<strong>Explanation: </strong>In this example, to maximize the number of resulting partitions we can leave s as it is.\nThe operations can now be performed as follows until s becomes empty: \n- Choose the longest prefix containing at most 3 distinct characters, "<u>aabaab</u>".\n- Delete the prefix, and s becomes empty. The number of partitions becomes 1. \nHence, the answer is 1. \nIt can be shown that it is not possible to obtain more than 1 partition.\n</pre>\n\n<p><strong class=\"example\">Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> s = "xxyz", k = 1\n<strong>Output:</strong> 4\n<strong>Explanation:</strong> In this example, to maximize the number of resulting partitions, s[1] can be changed to 'a'.\ns becomes "xayz".\nThe operations can now be performed as follows until s becomes empty:\n- Choose the longest prefix containing at most 1 distinct character, "<u>x</u>ayz".\n- Delete the prefix, and s becomes "ayz". The number of partitions is now 1.\n- Choose the longest prefix containing at most 1 distinct character, "<u>a</u>yz".\n- Delete the prefix, and s becomes "yz". The number of partitions is now 2.\n- Choose the longest prefix containing at most 1 distinct character, "<u>y</u>z".\n- Delete the prefix, and s becomes "z". The number of partitions is now 3.\n- Choose the longest prefix containing at most 1 distinct character, "<u>z</u>".\n- Delete the prefix, and s becomes empty. The number of partitions is now 4.\nHence, the answer is 4.\nIt can be shown that it is not possible to obtain more than 4 partitions.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= s.length <= 10<sup>4</sup></code></li>\n\t<li><code>s</code> consists only of lowercase English letters.</li>\n\t<li><code>1 <= k <= 26</code></li>\n</ul>\n",
|
|
"translatedTitle": null,
|
|
"translatedContent": null,
|
|
"isPaidOnly": false,
|
|
"difficulty": "Hard",
|
|
"likes": 58,
|
|
"dislikes": 12,
|
|
"isLiked": null,
|
|
"similarQuestions": "[{\"title\": \"Can Make Palindrome from Substring\", \"titleSlug\": \"can-make-palindrome-from-substring\", \"difficulty\": \"Medium\", \"translatedTitle\": null}]",
|
|
"exampleTestcases": "\"accca\"\n2\n\"aabaab\"\n3\n\"xxyz\"\n1",
|
|
"categoryTitle": "Algorithms",
|
|
"contributors": [],
|
|
"topicTags": [
|
|
{
|
|
"name": "String",
|
|
"slug": "string",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Dynamic Programming",
|
|
"slug": "dynamic-programming",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Bit Manipulation",
|
|
"slug": "bit-manipulation",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Bitmask",
|
|
"slug": "bitmask",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
}
|
|
],
|
|
"companyTagStats": null,
|
|
"codeSnippets": [
|
|
{
|
|
"lang": "C++",
|
|
"langSlug": "cpp",
|
|
"code": "class Solution {\npublic:\n int maxPartitionsAfterOperations(string s, int k) {\n \n }\n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Java",
|
|
"langSlug": "java",
|
|
"code": "class Solution {\n public int maxPartitionsAfterOperations(String s, int k) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Python",
|
|
"langSlug": "python",
|
|
"code": "class Solution(object):\n def maxPartitionsAfterOperations(self, s, k):\n \"\"\"\n :type s: str\n :type k: int\n :rtype: int\n \"\"\"\n ",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Python3",
|
|
"langSlug": "python3",
|
|
"code": "class Solution:\n def maxPartitionsAfterOperations(self, s: str, k: int) -> int:\n ",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "C",
|
|
"langSlug": "c",
|
|
"code": "int maxPartitionsAfterOperations(char* s, int k) {\n \n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "C#",
|
|
"langSlug": "csharp",
|
|
"code": "public class Solution {\n public int MaxPartitionsAfterOperations(string s, int k) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "JavaScript",
|
|
"langSlug": "javascript",
|
|
"code": "/**\n * @param {string} s\n * @param {number} k\n * @return {number}\n */\nvar maxPartitionsAfterOperations = function(s, k) {\n \n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "TypeScript",
|
|
"langSlug": "typescript",
|
|
"code": "function maxPartitionsAfterOperations(s: string, k: number): number {\n \n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "PHP",
|
|
"langSlug": "php",
|
|
"code": "class Solution {\n\n /**\n * @param String $s\n * @param Integer $k\n * @return Integer\n */\n function maxPartitionsAfterOperations($s, $k) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Swift",
|
|
"langSlug": "swift",
|
|
"code": "class Solution {\n func maxPartitionsAfterOperations(_ s: String, _ k: Int) -> Int {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Kotlin",
|
|
"langSlug": "kotlin",
|
|
"code": "class Solution {\n fun maxPartitionsAfterOperations(s: String, k: Int): Int {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Dart",
|
|
"langSlug": "dart",
|
|
"code": "class Solution {\n int maxPartitionsAfterOperations(String s, int k) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Go",
|
|
"langSlug": "golang",
|
|
"code": "func maxPartitionsAfterOperations(s string, k int) int {\n \n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Ruby",
|
|
"langSlug": "ruby",
|
|
"code": "# @param {String} s\n# @param {Integer} k\n# @return {Integer}\ndef max_partitions_after_operations(s, k)\n \nend",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Scala",
|
|
"langSlug": "scala",
|
|
"code": "object Solution {\n def maxPartitionsAfterOperations(s: String, k: Int): Int = {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Rust",
|
|
"langSlug": "rust",
|
|
"code": "impl Solution {\n pub fn max_partitions_after_operations(s: String, k: i32) -> i32 {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Racket",
|
|
"langSlug": "racket",
|
|
"code": "(define/contract (max-partitions-after-operations s k)\n (-> string? exact-integer? exact-integer?)\n )",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Erlang",
|
|
"langSlug": "erlang",
|
|
"code": "-spec max_partitions_after_operations(S :: unicode:unicode_binary(), K :: integer()) -> integer().\nmax_partitions_after_operations(S, K) ->\n .",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Elixir",
|
|
"langSlug": "elixir",
|
|
"code": "defmodule Solution do\n @spec max_partitions_after_operations(s :: String.t, k :: integer) :: integer\n def max_partitions_after_operations(s, k) do\n \n end\nend",
|
|
"__typename": "CodeSnippetNode"
|
|
}
|
|
],
|
|
"stats": "{\"totalAccepted\": \"1.3K\", \"totalSubmission\": \"5.7K\", \"totalAcceptedRaw\": 1286, \"totalSubmissionRaw\": 5662, \"acRate\": \"22.7%\"}",
|
|
"hints": [
|
|
"For each position, try to brute-force the replacements.",
|
|
"To speed up the brute-force solution, we can precompute the following (without changing any index) using prefix sums and binary search:<ul>\r\n<li><code>pref[i]</code>: The number of resulting partitions from the operations by performing the operations on <code>s[0:i]</code>.</li>\r\n<li><code>suff[i]</code>: The number of resulting partitions from the operations by performing the operations on <code>s[i:n - 1]</code>, where <code>n == s.length</code>.</li>\r\n<li><code>partition_start[i]</code>: The start index of the partition containing the <code>i<sup>th</sup></code> index after performing the operations.</li>\r\n</ul>",
|
|
"Now, for a position <code>i</code>, we can try all possible <code>25</code> replacements:<br />\r\nFor a replacement, using prefix sums and binary search, we need to find the rightmost index, <code>r</code>, such that the number of distinct characters in the range <code>[partition_start[i], r]</code> is at most <code>k</code>.<br />\r\nThere are <code>2</code> cases:<ul>\r\n<li><code>r >= i</code>: the number of resulting partitions in this case is <code>1 + pref[partition_start[i] - 1] + suff[r + 1]</code>.</li>\r\n<li>Otherwise, we need to find the rightmost index <code>r<sub>2</sub></code> such that the number of distinct characters in the range <code>[r:r<sub>2</sub>]</code> is at most <code>k</code>. The answer in this case is <code>2 + pref[partition_start[i] - 1] + suff[r<sub>2</sub> + 1]</code></li>\r\n</ul>",
|
|
"The answer is the maximum among all replacements."
|
|
],
|
|
"solution": null,
|
|
"status": null,
|
|
"sampleTestCase": "\"accca\"\n2",
|
|
"metaData": "{\n \"name\": \"maxPartitionsAfterOperations\",\n \"params\": [\n {\n \"name\": \"s\",\n \"type\": \"string\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"k\"\n }\n ],\n \"return\": {\n \"type\": \"integer\"\n }\n}",
|
|
"judgerAvailable": true,
|
|
"judgeType": "large",
|
|
"mysqlSchemas": [],
|
|
"enableRunCode": true,
|
|
"enableTestMode": false,
|
|
"enableDebugger": true,
|
|
"envInfo": "{\"cpp\": [\"C++\", \"<p>Compiled with <code> clang 11 </code> using the latest C++ 20 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level two optimization (<code>-O2</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>\"], \"java\": [\"Java\", \"<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\\r\\n\\r\\n<p>Note that Python 2.7 <a href=\\\"https://www.python.org/dev/peps/pep-0373/\\\" target=\\\"_blank\\\">will not be maintained past 2020</a>. For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 11</code> using the gnu11 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O2</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. Adding an item to a hash.</b>\\r\\n<pre>\\r\\nstruct hash_entry {\\r\\n int id; /* we'll use this field as the key */\\r\\n char name[10];\\r\\n UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>2. Looking up an item in a hash:</b>\\r\\n<pre>\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>3. Deleting an item in a hash:</b>\\r\\n<pre>\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n</pre>\\r\\n</p>\"], \"csharp\": [\"C#\", \"<p><a href=\\\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-12\\\" target=\\\"_blank\\\">C# 12</a> with .NET 8 runtime</p>\"], \"javascript\": [\"JavaScript\", \"<p><code>Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES6 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\\r\\n\\r\\n<p>For Priority Queue / Queue data structures, you may use 5.3.0 version of <a href=\\\"https://github.com/datastructures-js/priority-queue/tree/fb4fdb984834421279aeb081df7af624d17c2a03\\\" target=\\\"_blank\\\">datastructures-js/priority-queue</a> and 4.2.1 version of <a href=\\\"https://github.com/datastructures-js/queue/tree/e63563025a5a805aa16928cb53bcd517bfea9230\\\" target=\\\"_blank\\\">datastructures-js/queue</a>.</p>\"], \"ruby\": [\"Ruby\", \"<p><code>Ruby 3.2</code></p>\\r\\n\\r\\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>\"], \"swift\": [\"Swift\", \"<p><code>Swift 5.9</code>.</p>\"], \"golang\": [\"Go\", \"<p><code>Go 1.21</code></p>\\r\\n<p>Support <a href=\\\"https://github.com/emirpasic/gods/tree/v1.18.1\\\" target=\\\"_blank\\\">https://godoc.org/github.com/emirpasic/gods@v1.18.1</a> library.</p>\"], \"python3\": [\"Python3\", \"<p><code>Python 3.11</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/3/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/3/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/3/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\"], \"scala\": [\"Scala\", \"<p><code>Scala 2.13.7</code>.</p>\"], \"kotlin\": [\"Kotlin\", \"<p><code>Kotlin 1.9.0</code>.</p>\\r\\n\\r\\n<p>We are using an experimental compiler provided by JetBrains.</p>\"], \"rust\": [\"Rust\", \"<p><code>Rust 1.74.1</code></p>\\r\\n\\r\\n<p>Supports <a href=\\\"https://crates.io/crates/rand\\\" target=\\\"_blank\\\">rand </a> v0.6\\u00a0from crates.io</p>\"], \"php\": [\"PHP\", \"<p><code>PHP 8.2</code>.</p>\\r\\n<p>With bcmath module</p>\"], \"typescript\": [\"Typescript\", \"<p><code>TypeScript 5.1.6, Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2022</code></p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES2022 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\"], \"racket\": [\"Racket\", \"<p><a href=\\\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\\\" target=\\\"_blank\\\">Racket CS</a> v8.11</p>\\r\\n\\r\\n<p>Using <code>#lang racket</code></p>\\r\\n\\r\\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>\"], \"erlang\": [\"Erlang\", \"Erlang/OTP 26\"], \"elixir\": [\"Elixir\", \"Elixir 1.15 with Erlang/OTP 26\"], \"dart\": [\"Dart\", \"<p>Dart 3.2</p>\\r\\n\\r\\n<p>Your code will be run directly without compiling</p>\"]}",
|
|
"libraryUrl": null,
|
|
"adminUrl": null,
|
|
"challengeQuestion": null,
|
|
"__typename": "QuestionNode"
|
|
}
|
|
}
|
|
} |