{ "data": { "question": { "questionId": "2002", "questionFrontendId": "1872", "boundTopicId": null, "title": "Stone Game VIII", "titleSlug": "stone-game-viii", "content": "

Alice and Bob take turns playing a game, with Alice starting first.

\r\n\r\n

There are n stones arranged in a row. On each player's turn, while the number of stones is more than one, they will do the following:

\r\n\r\n
    \r\n\t
  1. Choose an integer x > 1, and remove the leftmost x stones from the row.
  2. \r\n\t
  3. Add the sum of the removed stones' values to the player's score.
  4. \r\n\t
  5. Place a new stone, whose value is equal to that sum, on the left side of the row.
  6. \r\n
\r\n\r\n

The game stops when only one stone is left in the row.

\r\n\r\n

The score difference between Alice and Bob is (Alice's score - Bob's score). Alice's goal is to maximize the score difference, and Bob's goal is the minimize the score difference.

\r\n\r\n

Given an integer array stones of length n where stones[i] represents the value of the ith stone from the left, return the score difference between Alice and Bob if they both play optimally.

\r\n\r\n

 

\r\n

Example 1:

\r\n\r\n
\r\nInput: stones = [-1,2,-3,4,-5]\r\nOutput: 5\r\nExplanation:\r\n- Alice removes the first 4 stones, adds (-1) + 2 + (-3) + 4 = 2 to her score, and places a stone of\r\n  value 2 on the left. stones = [2,-5].\r\n- Bob removes the first 2 stones, adds 2 + (-5) = -3 to his score, and places a stone of value -3 on\r\n  the left. stones = [-3].\r\nThe difference between their scores is 2 - (-3) = 5.\r\n
\r\n\r\n

Example 2:

\r\n\r\n
\r\nInput: stones = [7,-6,5,10,5,-2,-6]\r\nOutput: 13\r\nExplanation:\r\n- Alice removes all stones, adds 7 + (-6) + 5 + 10 + 5 + (-2) + (-6) = 13 to her score, and places a\r\n  stone of value 13 on the left. stones = [13].\r\nThe difference between their scores is 13 - 0 = 13.\r\n
\r\n\r\n

Example 3:

\r\n\r\n
\r\nInput: stones = [-10,-12]\r\nOutput: -22\r\nExplanation:\r\n- Alice can only make one move, which is to remove both stones. She adds (-10) + (-12) = -22 to her\r\n  score and places a stone of value -22 on the left. stones = [-22].\r\nThe difference between their scores is (-22) - 0 = -22.\r\n
\r\n\r\n

 

\r\n

Constraints:

\r\n\r\n", "translatedTitle": null, "translatedContent": null, "isPaidOnly": false, "difficulty": "Hard", "likes": 433, "dislikes": 22, "isLiked": null, "similarQuestions": "[{\"title\": \"Stone Game\", \"titleSlug\": \"stone-game\", \"difficulty\": \"Medium\", \"translatedTitle\": null}, {\"title\": \"Stone Game II\", \"titleSlug\": \"stone-game-ii\", \"difficulty\": \"Medium\", \"translatedTitle\": null}, {\"title\": \"Stone Game III\", \"titleSlug\": \"stone-game-iii\", \"difficulty\": \"Hard\", \"translatedTitle\": null}, {\"title\": \"Stone Game IV\", \"titleSlug\": \"stone-game-iv\", \"difficulty\": \"Hard\", \"translatedTitle\": null}, {\"title\": \"Stone Game V\", \"titleSlug\": \"stone-game-v\", \"difficulty\": \"Hard\", \"translatedTitle\": null}, {\"title\": \"Stone Game VI\", \"titleSlug\": \"stone-game-vi\", \"difficulty\": \"Medium\", \"translatedTitle\": null}, {\"title\": \"Stone Game VII\", \"titleSlug\": \"stone-game-vii\", \"difficulty\": \"Medium\", \"translatedTitle\": null}, {\"title\": \"Stone Game VIII\", \"titleSlug\": \"stone-game-viii\", \"difficulty\": \"Hard\", \"translatedTitle\": null}, {\"title\": \"Stone Game IX\", \"titleSlug\": \"stone-game-ix\", \"difficulty\": \"Medium\", \"translatedTitle\": null}]", "exampleTestcases": "[-1,2,-3,4,-5]\n[7,-6,5,10,5,-2,-6]\n[-10,-12]", "categoryTitle": "Algorithms", "contributors": [], "topicTags": [ { "name": "Array", "slug": "array", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Math", "slug": "math", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Dynamic Programming", "slug": "dynamic-programming", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Prefix Sum", "slug": "prefix-sum", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Game Theory", "slug": "game-theory", "translatedName": null, "__typename": "TopicTagNode" } ], "companyTagStats": null, "codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "class Solution {\npublic:\n int stoneGameVIII(vector& stones) {\n \n }\n};", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "class Solution {\n public int stoneGameVIII(int[] stones) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "class Solution(object):\n def stoneGameVIII(self, stones):\n \"\"\"\n :type stones: List[int]\n :rtype: int\n \"\"\"\n ", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class Solution:\n def stoneGameVIII(self, stones: List[int]) -> int:\n ", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "\n\nint stoneGameVIII(int* stones, int stonesSize){\n\n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\n public int StoneGameVIII(int[] stones) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {number[]} stones\n * @return {number}\n */\nvar stoneGameVIII = function(stones) {\n \n};", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "function stoneGameVIII(stones: number[]): number {\n\n};", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class Solution {\n\n /**\n * @param Integer[] $stones\n * @return Integer\n */\n function stoneGameVIII($stones) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "class Solution {\n func stoneGameVIII(_ stones: [Int]) -> Int {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "class Solution {\n fun stoneGameVIII(stones: IntArray): Int {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "func stoneGameVIII(stones []int) int {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# @param {Integer[]} stones\n# @return {Integer}\ndef stone_game_viii(stones)\n \nend", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "object Solution {\n def stoneGameVIII(stones: Array[Int]): Int = {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "impl Solution {\n pub fn stone_game_viii(stones: Vec) -> i32 {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "(define/contract (stone-game-viii stones)\n (-> (listof exact-integer?) exact-integer?)\n\n )", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"8.7K\", \"totalSubmission\": \"16.5K\", \"totalAcceptedRaw\": 8685, \"totalSubmissionRaw\": 16499, \"acRate\": \"52.6%\"}", "hints": [ "Let's note that the only thing that matters is how many stones were removed so we can maintain dp[numberOfRemovedStones]", "dp[x] = max(sum of all elements up to y - dp[y]) for all y > x" ], "solution": null, "status": null, "sampleTestCase": "[-1,2,-3,4,-5]", "metaData": "{\n \"name\": \"stoneGameVIII\",\n \"params\": [\n {\n \"name\": \"stones\",\n \"type\": \"integer[]\"\n }\n ],\n \"return\": {\n \"type\": \"integer\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

Compiled with clang 11 using the latest C++ 20 standard.

\\r\\n\\r\\n

Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

\\r\\n\\r\\n

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

\"], \"java\": [\"Java\", \"

OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

\\r\\n\\r\\n

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

\\r\\n

Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

\"], \"python\": [\"Python\", \"

Python 2.7.12.

\\r\\n\\r\\n

Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

\\r\\n\\r\\n

For Map/TreeMap data structure, you may use sortedcontainers library.

\\r\\n\\r\\n

Note that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.

\"], \"c\": [\"C\", \"

Compiled with gcc 8.2 using the gnu11 standard.

\\r\\n\\r\\n

Your code is compiled with level one optimization (-O1). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

\\r\\n\\r\\n

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

\\r\\n\\r\\n

For hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:

\\r\\n\\r\\n

1. Adding an item to a hash.\\r\\n

\\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
\\r\\n

\\r\\n\\r\\n

2. Looking up an item in a hash:\\r\\n

\\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
\\r\\n

\\r\\n\\r\\n

3. Deleting an item in a hash:\\r\\n

\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n    HASH_DEL(users, user);  \\r\\n}\\r\\n
\\r\\n

\"], \"csharp\": [\"C#\", \"

C# 10 with .NET 6 runtime

\"], \"javascript\": [\"JavaScript\", \"

Node.js 16.13.2.

\\r\\n\\r\\n

Your code is run with --harmony flag, enabling new ES6 features.

\\r\\n\\r\\n

lodash.js library is included by default.

\\r\\n\\r\\n

For Priority Queue / Queue data structures, you may use 5.3.0 version of datastructures-js/priority-queue and 4.2.1 version of datastructures-js/queue.

\"], \"ruby\": [\"Ruby\", \"

Ruby 3.1

\\r\\n\\r\\n

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

\"], \"swift\": [\"Swift\", \"

Swift 5.5.2.

\"], \"golang\": [\"Go\", \"

Go 1.21

\\r\\n

Support https://godoc.org/github.com/emirpasic/gods@v1.18.1 library.

\"], \"python3\": [\"Python3\", \"

Python 3.10.

\\r\\n\\r\\n

Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

\\r\\n\\r\\n

For Map/TreeMap data structure, you may use sortedcontainers library.

\"], \"scala\": [\"Scala\", \"

Scala 2.13.7.

\"], \"kotlin\": [\"Kotlin\", \"

Kotlin 1.9.0.

\"], \"rust\": [\"Rust\", \"

Rust 1.58.1

\\r\\n\\r\\n

Supports rand v0.6\\u00a0from crates.io

\"], \"php\": [\"PHP\", \"

PHP 8.1.

\\r\\n

With bcmath module

\"], \"typescript\": [\"Typescript\", \"

TypeScript 5.1.6, Node.js 16.13.2.

\\r\\n\\r\\n

Your code is run with --harmony flag, enabling new ES2022 features.

\\r\\n\\r\\n

lodash.js library is included by default.

\"], \"racket\": [\"Racket\", \"

Run with Racket 8.3.

\"]}", "libraryUrl": null, "adminUrl": null, "challengeQuestion": null, "__typename": "QuestionNode" } } }