SSSakshi Sharmainprefix-sum.hashnode.dev·Oct 3, 2025 · 3 min readPrefix Sum - 4LeetCode 724: Find Pivot Index – A Mathematical Prefix Sum Problem We’ve been solving prefix sum questions, and this one — Find Pivot Index — is actually more about mathematics than coding tricks. The problem says: Find an index where the sum of all...00
SSSakshi Sharmainprefix-sum.hashnode.dev·Oct 2, 2025 · 3 min readPrefix Sum -3Subarray Sum Equals K (Leetcode 560) – From Brute Force to HashMap When I saw this problem for the first time, honestly my mind just went:“Okay… subarray sum… let’s check all subarrays!” 😅That’s the brute force approach. Later I found the prefix sum...00
SSSakshi Sharmainprefix-sum.hashnode.dev·Oct 1, 2025 · 2 min readPrefix Sum -2LeetCode 724 — Find Pivot Index Author: Sakshi Sharma After learning the basics of prefix sums in the last blog (Running Sum problem), let’s step a little higher. Today’s problem is LeetCode 724: Find Pivot Index. It’s still beginner-friendly, but it...00
SSSakshi Sharmainprefix-sum.hashnode.dev·Oct 1, 2025 · 3 min readPrefix Sum -1Starting DSA with Prefix Sums — Running Sum of 1D Array (LeetCode 1480) Author: Sakshi Sharma When I began my DSA journey, I wanted a problem that felt like a warm-up jog — simple, useful, and the kind that builds intuition for many harder problems l...00