LeetCode 28. Find the Index of the First Occurrence in a String The Problem Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Examples Example 1: Input: haystack = "sadbutsad", needle = "sad" Output: 0 Explanation: "sad" occurs at index 0
LeetCode LeetCode: 14. Longest Common Prefix The Problem Write a function to find the longest common prefix string amongst an array of strings. If there is no common prefix, return an empty string "". Examples Example 1: Input: strs = ["flower","flow","flight"] Output: "fl" Example 2: Input:
LeetCode LeetCode: 58. Length of Last Word The Problem Given a string s consisting of words and spaces, return the length of the last word in the string. A word is a maximal substring consisting of non-space characters only. Example Example 1: Input: s = "Hello World" Output: 5 Explanation: The last word is "World&
LeetCode LeetCode: 13. Roman to Integer The Problem Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol ValueI 1 V 5 X 10 L 50 C 100 D 500 M 1000 For example, 2 is written as II in Roman numeral, just two ones added together. 12 is
LeetCode LeetCode: 121. Best Time to Buy and Sell Stock The Problem You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock. Return
LeetCode LeetCode: 169. Majority Element The Problem Given an array nums of size n, return the majority element. The majority element is the element that appears more than ⌊n / 2⌋ times. You may assume that the majority element always exists in the array. Example Example 1: Input: nums = [3,2,3] Output: 3 Example 2:
C++ A Beginner's Guide to Using Google Test for C++: Writing Reliable Unit Tests Made Easy! Google Test, developed by Google, is a robust C++ testing framework widely used for writing and executing automated unit tests. It offers a comprehensive suite of features and macros to simplify the process of creating and managing test cases. With Google Test, developers can ensure the reliability and stability of
LeetCode LeetCode: 26. Remove Duplicates from Sorted Array The Problem Given an integer array nums sorted in non-decreasing order, remove the duplicates in-place such that each unique element appears only once. The relative order of the elements should be kept the same. Then return the number of unique elements in nums. Consider the number of unique elements of
LeetCode LeetCode: 27. Remove Element The Problem Given an integer array nums and an integer val, remove all occurrences of val in nums in-place. The order of the elements may be changed. Then return the number of elements in nums which are not equal to val. Consider the number of elements in nums which are
LeetCode LeetCode: 88. Merge Sorted Array The Problem You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and nums2 respectively. Merge nums1 and nums2 into a single array sorted in non-decreasing order. The final sorted array should not be
LeetCode LeetCode: 69. Sqrt(x) The Problem Given a non-negative integer x, return the square root of x rounded down to the nearest integer. The returned integer should be non-negative as well. You must not use any built-in exponent function or operator. * For example, do not use pow(x, 0.5) in c++ or x
Python Packages 101: A Developer's Journey from Code to Community Welcome to the world of unlocking the full potential of your Python code! Python, known for its simplicity and readability, also shines in its versatility. A game-changer for Python is its knack for creating and sharing packages—bundles of code that can be easily shared, reused, and collaborated on. Why
LeetCode LeetCode: 437. Path Sum III The Problem Given the root of a binary tree and an integer targetSum, return the number of paths where the sum of the values along the path equals targetSum. The path does not need to start or end at the root or a leaf, but it must go downwards (i.
LeetCode LeetCode: 337. House Robber III The Problem The thief has found himself a new place for his thievery again. There is only one entrance to this area, called root. Besides the root, each house has one and only one parent house. After a tour, the smart thief realized that all houses in this place form
LeetCode LeetCode: 331. Verify Preorder Serialization of a Binary Tree The Problem One way to serialize a binary tree is to use preorder traversal. When we encounter a non-null node, we record the node's value. If it is a null node, we record using a sentinel value such as '#'. Example The above binary tree can be
LeetCode LeetCode: 236. Lowest Common Ancestor of a Binary Tree The Problem Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has both p and
LeetCode LeetCode: 235. Lowest Common Ancestor of a Binary Search Tree The Problem Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has
LeetCode LeetCode: 230. Kth Smallest Element in a BST The Problem Given the root of a binary search tree, and an integer k, return thekthsmallest value (1-indexed) of all the values of the nodes in the tree. Example Input: [3,1,4,null,2], k = 1 Output: 1 Constraints: * The number of nodes in the tree is n. * 1
LeetCode LeetCode: 199. Binary Tree Right Side View The Problem Given the root of a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom. Example Input: root = [1,2,3,null,5,null,4] Output: [1,3,4] Solution We opted for
LeetCode LeetCode: 173. Binary Search Tree Iterator The Problem Implement the BSTIterator class that represents an iterator over the in-order traversal of a binary search tree (BST): * BSTIterator(TreeNode root) Initializes an object of the BSTIterator class. The root of the BST is given as part of the constructor. The pointer should be initialized to a non-existent
iOS SwiftUI Animation Essentials: Nailing the Basics Imagine your mobile apps doing more than just sitting still. With SwiftUI, animations breathe life into your app effortlessly. Welcome to 'SwiftUI Animation Essentials.' This guide simplifies animation basics, perfect for beginners or seasoned developers. Animations add charm, and SwiftUI makes it easy. Whether you're new
LeetCode LeetCode: 129. Sum Root to Leaf Numbers The Problem You are given the root of a binary tree containing digits from 0 to 9 only. Each root-to-leaf path in the tree represents a number. For example, the root-to-leaf path 1 -> 2 -> 3 represents the number 123. Return the total sum of all root-to-leaf
LeetCode LeetCode: 117. Populating Next Right Pointers in Each Node II The Problem Given a binary tree struct Node { int val; Node *left; Node *right; Node *next; } Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially, all next pointers are set to NULL.
LeetCode LeetCode: 116. Populating Next Right Pointers in Each Node The Problem You are given a perfect binary tree where all leaves are on the same level, and every parent has two children. The binary tree has the following definition: struct Node { int val; Node *left; Node *right; Node *next; } Populate each next pointer to point to its next right
LeetCode LeetCode: 114. Flatten Binary Tree to Linked List The Problem Given the root of a binary tree, flatten the tree into a "linked list": * The "linked list" should use the same TreeNode class where the right child pointer points to the next node in the list and the left child pointer is always null.
