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Diameter Of Binary Tree

Diameter Of a Binary Tree Given the root of a binary tree, return the length of the diameter of the tree. The diameter of a binary tree is the length of the longes path between any two nodes in a...

Permutations

Permutations Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order. Example: \( [1, 2, 3] \to 1, 2, 3], [1, 3, 2], [2, 1, 3], [2,...

Remove Duplicates From Sorted Array

Given an integer array nums, sorted in nondecreasing order, remove some duplicates inplace such that each unique element appears at most twice. The relative order of the elements should be kept the...

Karen and Coffee

You know n coffee recipes, and the ith recipe suggests that coffee should be brewed between $l_i$ and $r_i$ degrees, inclusive, to achieve the optimal taste. Karen thinks that a temperature is admi...

01 Tree

There is an edgeweighted complete binary tree with n leaves. A complete binary tree is defined as a tree where every nonleaf vertex has exactly 2 children. For each nonleaf vertex, we label one of ...

Grouping Increases

You are given an array a of size n. You will do the following process to calculate your penalty: Split array \(a\) into two (possibly empty) subsequences \(s\) and \(t\) such that every element ...

Gas Station

There are n gas stations along a circular route, where the amount of gas at the i'th station is gas[i]. You have a car with an unlimited gas tank, and it costs cost[i] to travel from the ith s...

Candy (Peaks and Valleys)

Candy There are n children standing in a line. Each child is assigned a rating value given in the integer array ratings. You are giving candies to these children subjected to the following requir...

Substring With Concatenation Of All Words

Substring With Concatenation Of All Words You are given a string s, and an array of strings words. All the strings of words are of the same length A concatenated substring in s is a substring tha...

Reverse Nodes In K-Group

Reverse Nodes In KGroup Given the head of a linked list, reverse the nodes of the list k at a time, without altering the value of any nodes in the list. If the number of nodes is not a multiple of ...

LeetCode Problems

LeetCode Problems! LC 23: Merge K Lists LC 25: Reverse Nodes In KGroup LC 32: Longest Valid Parentheses

Longest Valid Parentheses

Longest Valid Parentheses You are given a string s containing just the characters '(' and ')'. return the length of the longest valid (wellformed) parentheses substring Examples In...

Merge K Lists

Merge K Lists You are given an array of k linkedlists lists, where each linked list is sorted in ascending order. merge all the linkedlists into one sorted linkedlist and return it /** * Definitio...