{ "data": { "question": { "questionId": "2414", "questionFrontendId": "2337", "boundTopicId": null, "title": "Move Pieces to Obtain a String", "titleSlug": "move-pieces-to-obtain-a-string", "content": "

You are given two strings start and target, both of length n. Each string consists only of the characters 'L', 'R', and '_' where:

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Return true if it is possible to obtain the string target by moving the pieces of the string start any number of times. Otherwise, return false.

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Example 1:

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\nInput: start = "_L__R__R_", target = "L______RR"\nOutput: true\nExplanation: We can obtain the string target from start by doing the following moves:\n- Move the first piece one step to the left, start becomes equal to "L___R__R_".\n- Move the last piece one step to the right, start becomes equal to "L___R___R".\n- Move the second piece three steps to the right, start becomes equal to "L______RR".\nSince it is possible to get the string target from start, we return true.\n
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Example 2:

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\nInput: start = "R_L_", target = "__LR"\nOutput: false\nExplanation: The 'R' piece in the string start can move one step to the right to obtain "_RL_".\nAfter that, no pieces can move anymore, so it is impossible to obtain the string target from start.\n
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Example 3:

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\nInput: start = "_R", target = "R_"\nOutput: false\nExplanation: The piece in the string start can move only to the right, so it is impossible to obtain the string target from start.
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Constraints:

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Compiled with clang 11 using the latest C++ 17 standard.

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

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

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

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

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

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Python 2.7.12.

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

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

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

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Compiled with gcc 8.2 using the gnu11 standard.

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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.

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

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

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

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\\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

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Node.js 16.13.2.

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

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lodash.js library is included by default.

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

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Ruby 3.1

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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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Swift 5.5.2.

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Go 1.17.6.

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

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Python 3.10.

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

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

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Scala 2.13.7.

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Kotlin 1.3.10.

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Rust 1.58.1

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Supports rand v0.6\\u00a0from crates.io

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PHP 8.1.

\\r\\n

With bcmath module

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

TypeScript 4.5.4, Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES2020 features.

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lodash.js library is included by default.

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Run with Racket 8.3.

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