Pivot Index Interview Question | JavaScript DSA
In this video, we solve LeetCode 724: Find Pivot Index using JavaScript.
This interview question introduces the Running Sum pattern, an important technique that later leads to Prefix Sum problems.
We'll first understand what a Pivot Index actually means, then solve the problem step by step with a beginner-friendly explanation and dry run.
Topics Covered:
Understanding the Problem Statement
What is a Pivot Index?
Running Sum Pattern
Optimized O(n) Solution
Step-by-Step Dry Run
Time Complexity Analysis
Space Complexity Analysis
Interview Explanation
Problem:
Given an integer array nums, return the pivot index.
The pivot index is the index where the sum of all elements to the left is equal to the sum of all elements to the right.
Note:
The pivot element itself is NOT included in either the left sum or the right sum.
Example:
Input:
[1,7,3,6,5,6]
Output:
3
Explanation:
Left Sum = 1 + 7 + 3 = 11
Right Sum = 5 + 6 = 11
Algorithm Used:
Array Traversal
Running Sum
Time Complexity:
O(n)
Space Complexity:
O(1)
Language:
JavaScript
This video is part of the JavaScript DSA Interview Preparation Playlist where we solve real interview questions from LeetCode, HackerRank, and NeetCode with step-by-step explanations designed for beginners and interview preparation.
#javascript #leetcode #dsa #codinginterview #arrays #programming #javascriptdeveloper
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