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Given a nonempty array of integers nums, every element appears twice except for one. Find that single one. Constraints The array nums will always contain exactly one element that appears only once. Your algorithm should have a linear runtime complexity. Can you implement it witho…
Learn how to implement Shell Sort in JavaScript, an optimized version of insertion sort using a shrinking gap sequence.
Learn how to implement Radix Sort in JavaScript, sorting integers digit by digit using a stable counting sort at each step.
Learn how to implement Counting Sort in JavaScript, a non-comparison sorting algorithm with O(n + k) time complexity.
Learn how to implement Insertion Sort in JavaScript, building the sorted array one element at a time, with code and sample output.
Learn how to implement Selection Sort in JavaScript by repeatedly selecting the minimum element, with code and sample output.
Learn how to implement Bubble Sort in JavaScript, the simplest sorting algorithm to understand, with code and sample output.
Learn how to find the smallest subarray with a sum at least equal to a target in JavaScript using the Sliding Window technique.
Learn how to find the longest substring without repeating characters in JavaScript using a variable-size Sliding Window.
Learn the Sliding Window technique in JavaScript by solving the maximum sum subarray of size K problem in O(n) time.
Learn how to implement Heap Sort in JavaScript using a binary heap, with guaranteed O(n log n) performance, code, and output.
Learn how to implement Quick Sort in JavaScript using pivot-based partitioning, with code, output, and interview FAQs.
Learn how to implement Merge Sort in JavaScript, a divide-and-conquer sorting algorithm with guaranteed O(n log n) time complexity.
Python remains the dominant language for AI and machine learning in 2026. Here's why its ecosystem keeps it ahead despite new languages and AI-agent frameworks.
Learn how to implement linear regression from scratch in Python without scikit-learn, using the Ordinary Least Squares formula.
Learn how to build a simple rule-based AI chatbot in Python using keyword matching, with code and sample conversation output.
Given an array of strings strs, group the anagrams together. You can return the answer in any order. An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. Constraints: 1 <= strs.lengt…
Given an integer n, return the number of prime numbers that are strictly less than n.A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.For example, 2, 3, 5, 7 are prime numbers, but 4, 6, 8, 9 are not. Constraints 0 <= n <= 5…
Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same element twice. Constraints: 2 <= nums.length <= 10^4 10^9 <= nums…
Given an array of strings strs, find the longest common prefix among all strings in the array.If there is no common prefix, return an empty string "". Input: strs is an array of strings. Constraints: 1 <= strs.length <= 200 0 <= strs[i].length <= 200 strs[i] consists of only lowe…