{ "data": { "question": { "questionId": "1228", "questionFrontendId": "1130", "boundTopicId": null, "title": "Minimum Cost Tree From Leaf Values", "titleSlug": "minimum-cost-tree-from-leaf-values", "content": "

Given an array arr of positive integers, consider all binary trees such that:

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Among all possible binary trees considered, return the smallest possible sum of the values of each non-leaf node. It is guaranteed this sum fits into a 32-bit integer.

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A node is a leaf if and only if it has zero children.

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Example 1:

\n\"\"\n
\nInput: arr = [6,2,4]\nOutput: 32\nExplanation: There are two possible trees shown.\nThe first has a non-leaf node sum 36, and the second has non-leaf node sum 32.\n
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Example 2:

\n\"\"\n
\nInput: arr = [4,11]\nOutput: 44\n
\n\n

 

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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 gnu99 standard.

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

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

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C# 10 with .NET 6 runtime

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Your code is compiled with debug flag enabled (/debug).

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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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Python 3.10.

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Rust 1.58.1

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