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There are a row of n houses, each house can be painted with one of the three colors: red, blue or green. The cost of painting each house with a certai 阅读全文
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Given two strings s and t, you want to transform string s into string t using the following operation any number of times: Choose a non-empty substrin 阅读全文
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Given an integer array arr, remove a subarray (can be empty) from arr such that the remaining elements in arr are non-decreasing. A subarray is a cont 阅读全文
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I have run into 2 different problems that can be solved using binary lifting. Then there is second thread's tree basics youtube video that talks about 阅读全文
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Given an array arr that represents a permutation of numbers from 1 to n. You have a binary string of size n that initially has all its bits set to zer 阅读全文
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Given an integer n and an integer array rounds. We have a circular track which consists of n sectors labeled from 1 to n. A marathon will be held on t 阅读全文
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On a broken calculator that has a number showing on its display, we can perform two operations: Double: Multiply the number on the display by 2, or; D 阅读全文
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Your task is to form an integer array nums from an initial array of zeros arr that is the same size as nums. Return the minimum number of function cal 阅读全文
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Given two arrays of length m and n with digits 0-9 representing two numbers. Create the maximum number of length k <= m + n from digits of the two. Th 阅读全文
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In universe Earth C-137, Rick discovered a special form of magnetic force between two balls if they are put in his new invented basket. Rick has n emp 阅读全文