Array

Consecutive Characters

Find the power of a string—the length of the longest substring with a single repeated character. Efficient O(n) solutions use either single traversal counting or a two-pointer approach.

Number of Zero-Filled Subarrays

Finding Pairs With a Certain Sum

Efficiently count pairs with a given sum from two arrays using hashing. Optimize queries with a frequency map for nums2, handling updates and counts in real-time.

Find the Lucky Integer in an Array

Learn multiple efficient approaches to find the largest lucky integer in an array, where a lucky number equals its frequency. Includes C++ code, examples, and complexity analysis.

Find the Original Typed String 1

Efficient C++ algorithm to count possible original strings from a clumsy typed input where a key may have been long-pressed once. Uses O(n) time and O(1) space for optimal performance.

Maximum Difference Between Adjacent Elements in a Circular Array

Learn how to find the maximum absolute difference between adjacent elements in a circular array using efficient C++ code. This guide covers logic, implementation, and time-space complexity in O(n) time.

Maximum Difference Between Even and Odd Frequency 1

Is Subsequence

Learn how to check if one string is a subsequence of another using two pointers, recursion, and memoization. Efficient C++ solutions with dry runs and complexity analysis included.

Squares of a Sorted Array

Learn how to efficiently square and sort a non-decreasing integer array using a two-pointer technique. This optimal solution runs in O(n) time with O(1) extra space, making it perfect for handling large datasets smoothly.

Remove Duplicates from Sorted Array 2

Partition Array Into Three Parts With Equal Sum