{ "data": { "question": { "questionId": "2044", "questionFrontendId": "1915", "boundTopicId": null, "title": "Number of Wonderful Substrings", "titleSlug": "number-of-wonderful-substrings", "content": "
A wonderful string is a string where at most one letter appears an odd number of times.
\r\n\r\n"ccjjc"
and "abab"
are wonderful, but "ab"
is not.Given a string word
that consists of the first ten lowercase English letters ('a'
through 'j'
), return the number of wonderful non-empty substrings in word
. If the same substring appears multiple times in word
, then count each occurrence separately.
A substring is a contiguous sequence of characters in a string.
\r\n\r\n\r\n
Example 1:
\r\n\r\n\r\nInput: word = "aba"\r\nOutput: 4\r\nExplanation: The four wonderful substrings are underlined below:\r\n- "aba" -> "a"\r\n- "aba" -> "b"\r\n- "aba" -> "a"\r\n- "aba" -> "aba"\r\n\r\n\r\n
Example 2:
\r\n\r\n\r\nInput: word = "aabb"\r\nOutput: 9\r\nExplanation: The nine wonderful substrings are underlined below:\r\n- "aabb" -> "a"\r\n- "aabb" -> "aa"\r\n- "aabb" -> "aab"\r\n- "aabb" -> "aabb"\r\n- "aabb" -> "a"\r\n- "aabb" -> "abb"\r\n- "aabb" -> "b"\r\n- "aabb" -> "bb"\r\n- "aabb" -> "b"\r\n\r\n\r\n
Example 3:
\r\n\r\n\r\nInput: word = "he"\r\nOutput: 2\r\nExplanation: The two wonderful substrings are underlined below:\r\n- "he" -> "h"\r\n- "he" -> "e"\r\n\r\n\r\n
\r\n
Constraints:
\r\n\r\n1 <= word.length <= 105
word
consists of lowercase English letters from 'a'
to 'j'
.Compiled with clang 11
using the latest C++ 20 standard.
Your code is compiled with level two optimization (-O2
). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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Python 2.7.12
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\\r\\n\\r\\nFor Map/TreeMap data structure, you may use sortedcontainers library.
\\r\\n\\r\\nNote that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.
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Most standard library headers are already included automatically for your convenience.
\\r\\n\\r\\nFor hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:
\\r\\n\\r\\n1. 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
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Node.js 16.13.2
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Your code is run with --harmony
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lodash.js library is included by default.
\\r\\n\\r\\nFor 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.
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Go 1.21
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