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Mastering Fenwick Tree for Competitive Programming

Feb 23 · 11 min read · While reading, don’t overthink or get stuck. Just follow along with the flow—you’ll understand everything step by step as we go. Given ArrayIndex : 0 1 2 3 4 5 6Array : 3 2

Mo’s Algorithm – Step by Step Guide

Feb 21 · 10 min read · Mo’s Algorithm is a technique used to answer range queries efficiently on arrays You are given : An array A Many queries: [L, R] Each query asks something like : sum of elements number of dis

Efficient Range Queries Using Sqrt Decomposition

Feb 21 · 6 min read · Square Root Decomposition is a technique used to answer range queries efficiently. When do we use it? When you have : An array A[0…N-1] Many queries like : Sum of range [L, R] Min/Max in range C

Essential Math Algorithms for Competitive Coding

Feb 16 · 7 min read · Binary Exponentiation : is a fast method to calculate powers like aⁿ , without multiplying a again and again n times. Instead of O(n) multiplications, it works in O(log n) time. Idea Behind Binary Exponentiation We use two simple observations : If po...

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Understanding Binary Exponentiation

Feb 14 · 1 min read · The idea behind is simple. We want to calculate, in the fastest way, a number raised another $$a^n$$Naive Implementation

Sweep Line Technique : The Secret Weapon for Range & Geometry Problems , Part-2

Feb 14 · 4 min read · Sweep Line Ideas : Question :-Given N Intervals Of The Form -> L,RN<=10^5L,R <= 10^9 1 - Find Union Of All :The union of two sets contains all elements from both sets, with common elements included only once Example :Intervals : [1,5] [3,7] Numb...

Sweep Line Technique : The Secret Weapon for Range & Geometry Problems , Part-1

Feb 13 · 9 min read · Interval : An Interval is a continuous range of values between a start point and an end point on a lineExample :[1, 5) means the interval starts at 1 and goes up to 5, but does not include 5 Event : An Event is a specific point where an interval sta...

Contribution Technique – The Secret Trick to Faster DSA Solutions

Feb 11 · 7 min read · Contribution Technique Contribution Technique is an optimization method in Data Structures & Algorithms where we calculate how much each element contributes to the final answer instead of generating all subarrays.It helps reduce time complexity from ...

Prefix Sum & Difference Array – Basic Level Guide

Feb 10 · 4 min read · Prefix Sum It is a simple yet powerful technique that allows to perform fast calculation on the sum of elements in a given range (called contiguous segments of array) A Prefix Sum Array stores the cumulative sum of elements from the start up to the c...

Mastering Modular Arithmetic & Why 10⁹+7 Matters in Competitive Programming

Feb 9 · 16 min read · What is modulo : Modulo arithmetic is a mathematical operation that deals with remainders. When dividing one integer by another, we typically get a quotient and a remainder. This concept is formalized with the notation n%m, where n is the dividend an...