Coding Problems

Sharpen your coding skills with a collection of interactive programming challenges. Write code, run test cases, and master algorithms directly in your browser. If you wish to submit a new problem, please open a pull request. https://github.com/SidharthArya/practicedsa

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Array Dynamic Programming Hash Table Linked List Manacher's Algorithm Math Recursion String Two Pointers

Add Two Numbers
medium

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.

Longest Palindrome Substring
medium

Given a string s, return the longest palindromic substring in s.

Two Sum
easy

Given an array of integers `nums` and an integer `target`, return indices of the two numbers such that they add up to `target`.