Pivot Index – From Brute Force to Optimal Approach | Prefix Sum | C++, Java, Python
In this video, we solve the Pivot Index problem step by step starting from the brute force approach and then moving to the optimized solution.
First, we understand the basic idea of checking left sum and right sum for every index and why the brute force solution is inefficient. Then we build the optimal approach using prefix sum logic to reduce the time complexity.
In this video we cover:
Brute force approach and intuition
Why recalculating left and right sums is inefficient
Key observation that leads to optimization
How to use total sum and running sum to find the pivot index
Clean implementation in C++, Java, and Python
This problem is a great way to understand how prefix sum can help optimize problems that involve repeated range sum calculations.
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