Two Sum and Sorted Two Sum

Introduction The Two Sum problem is one of the most popular questions in programming interviews. It helps in understanding arrays, hashing, and two-pointer techniques. Problem Statement Two Sum Given an array of integers and a target value, return the indices of the two numbers such that they add up to the target. Two Sum II (Sorted Array) Given a sorted array, find two numbers such that they add up to a target. Return their indices. 💡 Approach 1: Two Sum (Using Hash Map) Create a dictionary to store numbers and their indices For each element: Find complement = target - element Check if complement exists in dictionary If yes → return indices Python Code (Two Sum) python def two_sum(nums, target): hashmap = {} for i, num in enumerate(nums): complement = target - num if complement in hashmap: return [hashmap[complement], i] hashmap[num] = i Approach 2: Two Sum II (Sorted Array - Two Pointer) Use two pointers: left = 0 right = n - 1 Calculate sum: If sum == target → return indices If sum