Arrays
Master array manipulation with fundamental problems covering searching, sorting, and advanced algorithms.
Showing 21 of 21 questions
Easy: 11 Medium: 8 Hard: 2
| Question | Difficulty |
|---|---|
Buy and Sell Stock (Maximum Profit) Find the maximum profit from buying and selling stock with at most one transaction | Easy |
Check if Array is Sorted Determine if an array is sorted in ascending, descending, or not sorted at all | Easy |
Find the Maximum Element in an Array Find and return the largest element in an array of integers | Easy |
Find Missing Number (1 to n) Find the missing number in an array containing n distinct numbers taken from 1, 2, 3, ..., n+1 | Easy |
Intersection of Two Arrays Find the intersection of two arrays and return the result as an array. | Easy |
Find Majority Element (Boyer-Moore Algorithm) Find the majority element that appears more than n/2 times using Boyer-Moore majority vote algorithm | Easy |
Merge Two Sorted Arrays Merge two sorted arrays into a single sorted array in-place | Easy |
Move All Zeros to the End Move all zeros in an array to the end while maintaining the relative order of non-zero elements | Easy |
Reverse an Array Reverse the order of elements in an array in-place and return the modified array | Easy |
Find the Second Largest Element in an Array Find and return the second largest element in an array of integers | Easy |
Two Sum Find two numbers in an array that add up to a target value. | Easy |
Find Duplicate Number Find the duplicate number in an array containing n+1 integers where each integer is between 1 and n (inclusive) | Medium |
Longest Consecutive Sequence Find the length of the longest consecutive elements sequence in an unsorted array. | Medium |
Maximum Subarray Sum (Kadane's Algorithm) Find the contiguous subarray with maximum sum using Kadane's algorithm | Medium |
Minimum Swaps to Sort Array Find the minimum number of swaps required to sort an array. | Medium |
Product of Array Except Self Return an array where each element is the product of all elements except the element at that index. | Medium |
Rotate Array by K Steps Rotate an array to the right by k steps where k is non-negative | Medium |
Subarray with Given Sum Find a subarray with a given sum in an array of positive integers. | Medium |
Three Sum (Triplets that Sum to Zero) Find all unique triplets in the array which gives the sum of zero | Medium |
Sliding Window Maximum Find the maximum element in each sliding window of size k | Hard |
Trapping Rain Water Calculate how much rainwater can be trapped between bars of different heights | Hard |