You need to find the largest value in each row of a binary tree.

Return any binary tree that matches the given preorder and postorder traversals.

Given two integers L and R, find the count of numbers in the range [L, R] (inclusive) having a prime number of set bits in their binary representation.

Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.

给定两个非负整数 x 和 y，如果某一整数等于 x^i + y^j，其中整数 i >= 0 且 j >= 0，那么我们认为该整数是一个强整数。 返回值小于或等于 bound 的所有强整数组成的列表。 你可以按任何顺序返回答案。在你…

You have an array of logs. Each log is a space delimited string of words.

Given a list of daily temperatures T, return a list such that, for each day in the input, tells you how many days you would have to wait until a warmer temperature. If there is no future day for wh…

Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array.

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Given an n-ary tree, return the level order traversal of its nodes’ values. (ie, from left to right, level by level).