{ "data": { "question": { "questionId": "2854", "questionFrontendId": "2746", "boundTopicId": null, "title": "Decremental String Concatenation", "titleSlug": "decremental-string-concatenation", "content": "
You are given a 0-indexed array words
containing n
strings.
Let's define a join operation join(x, y)
between two strings x
and y
as concatenating them into xy
. However, if the last character of x
is equal to the first character of y
, one of them is deleted.
For example join("ab", "ba") = "aba"
and join("ab", "cde") = "abcde"
.
You are to perform n - 1
join operations. Let str0 = words[0]
. Starting from i = 1
up to i = n - 1
, for the ith
operation, you can do one of the following:
stri = join(stri - 1, words[i])
stri = join(words[i], stri - 1)
Your task is to minimize the length of strn - 1
.
Return an integer denoting the minimum possible length of strn - 1
.
\n
Example 1:
\n\n\nInput: words = ["aa","ab","bc"]\nOutput: 4\nExplanation: In this example, we can perform join operations in the following order to minimize the length of str2: \nstr0 = "aa"\nstr1 = join(str0, "ab") = "aab"\nstr2 = join(str1, "bc") = "aabc" \nIt can be shown that the minimum possible length of str2 is 4.\n\n
Example 2:
\n\n\nInput: words = ["ab","b"]\nOutput: 2\nExplanation: In this example, str0 = "ab", there are two ways to get str1: \njoin(str0, "b") = "ab" or join("b", str0) = "bab". \nThe first string, "ab", has the minimum length. Hence, the answer is 2.\n\n\n
Example 3:
\n\n\nInput: words = ["aaa","c","aba"]\nOutput: 6\nExplanation: In this example, we can perform join operations in the following order to minimize the length of str2: \nstr0 = "aaa"\nstr1 = join(str0, "c") = "aaac"\nstr2 = join("aba", str1) = "abaaac"\nIt can be shown that the minimum possible length of str2 is 6.\n\n\n
\n
Constraints:
\n\n1 <= words.length <= 1000
1 <= words[i].length <= 50
words[i]
is an English lowercase letterCompiled 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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\\r\\n\\r\\nFor hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:
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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.
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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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Go 1.21
Support https://godoc.org/github.com/emirpasic/gods@v1.18.1 library.
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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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Kotlin 1.9.0
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Rust 1.58.1
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With bcmath module
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Dart 2.17.3
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