Range Sum Query – Immutable Explained 💡 | Prefix Sum Pattern | DSA Telugu Ep.43

Welcome to DSA Telugu Series – Episode 43 💻🔥 In this video, we solve Range Sum Query – Immutable, one of the most important applications of the Prefix Sum pattern. If you understood Running Sum in the previous episode, this problem will show you the real power of Prefix Sum in answering multiple queries efficiently. 📘 What You’ll Learn What is Range Sum Query? Why brute force is inefficient How Prefix Sum helps answer queries in O(1) Preprocessing concept explained Step-by-step example Code implementation Time Complexity & Space Complexity 💡 Core Idea Instead of calculating sum for every query repeatedly, We build a Prefix Sum array once, and then: Sum from index L to R = prefix[R] − prefix[L − 1] This reduces query time from O(n) to O(1). 🎓 Why This Problem Is Important Range Sum Query is the base for: Subarray Sum Equals K Subarrays Divisible by K Count of Range Sum Advanced segment tree problems This is a must-know concept for coding interviews and placements. range sum query range sum query immutable range sum query prefix sum range sum query explained range sum query tutorial range sum query dsa range sum query array range sum query problem range sum query leetcode range sum query implementation range sum query time complexity range sum query example range sum query telugu range sum query immutable telugu prefix sum telugu range sum query dsa telugu prefix sum pattern telugu array problems telugu range sum query tutorial telugu dsa telugu series coding for beginners telugu subarray problems telugu how to solve range sum query range sum query immutable explained range sum query using prefix sum range sum query step by step range sum query coding interview question range sum query time and space complexity range sum query implementation in java range sum query implementation in python range sum query implementation in c++ range sum query beginner dsa problem #dsaintelugu #telugucoding #programmingintelugu #dsa #datastructures #algorithms