LeetCode 700. Search in a Binary Search Tree
Description https://leetcode.com/problems/swap-nodes-in-pairs/ You are given the root of a binary search tree (BST) and an integer val. Find the node in the BST…
LeetCode 1683. Invalid Tweets
Description https://leetcode.com/problems/invalid-tweets/ Table: Tweets +—————-+———+ | Column Name | Type | +—————-+———+ | tweet_id | int | | content | varchar…
LeetCode 24. Swap Nodes in Pairs
Description https://leetcode.com/problems/swap-nodes-in-pairs/ Given a linked list, swap every two adjacent nodes and return its head. Example 1: Input: head = [1,2,3,4]…
LeetCode 1464. Maximum Product of Two Elements in an Array
Description https://leetcode.com/problems/maximum-product-of-two-elements-in-an-array/ Given the array of integers nums, you will choose two different indices i and j of that array. Return the maximum value of(nums[i]-1)*(nums[j]-1). Example…
LeetCode 509. Fibonacci Number
Description https://leetcode.com/problems/fibonacci-number/ The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the…
Backtracking
Backtracking is an algorithm for finding all solutions by exploring all potential candidates. If the solution candidate turns to be not a solution,…
LeetCode 410. Split Array Largest Sum
Description https://leetcode.com/problems/split-array-largest-sum/ Given an array nums which consists of non-negative integers and an integer m, you can split the array into m non-empty continuous subarrays.…
LeetCode 315. Count of Smaller Numbers After Self
Description https://leetcode.com/problems/count-of-smaller-numbers-after-self/ You are given an integer array nums and you have to return a new counts array. The counts array has the property where counts[i] is the…
LeetCode 833. Find And Replace in String
Description https://leetcode.com/problems/find-and-replace-in-string/ To some string S, we will perform some replacement operations that replace groups of letters with new ones (not necessarily the…
LeetCode 951. Flip Equivalent Binary Trees
Description https://leetcode.com/problems/flip-equivalent-binary-trees/ For a binary tree T, we can define a flip operation as follows: choose any node, and swap the left and…