Are you stuck on the “Largest subarray with 0 sum” problem from GeeksforGeeks? Don\u2019t worry! In this blog, we\u2019ll explain the problem, walk you through both brute force and optimal solutions, and make everything easy to understand with comments, dry runs, and clear explanations.<\/p>\n\n\n\n
Here’s the [Problem Link<\/span><\/mark><\/a><\/strong>] to begin with.<\/p>\n\n\n You are given an array of integers. Your task is to find the length of the largest subarray (continuous part of the array) whose elements sum up to 0.<\/p>\n\n\n\n Input:<\/strong> Output:<\/strong> Explanation:<\/strong> Input:<\/strong> Output:<\/strong> Explanation:<\/strong> Let\u2019s solve the problem step by step in the simplest way:<\/p>\n\n\n\n This approach is easy to understand but not efficient for large arrays.<\/p>\n\n\n\nWhat Does the Problem Say?<\/h2>\n\n\n\n
Example 1<\/h3>\n\n\n\n
arr = [15, -2, 2, -8, 1, 7, 10, 23]<\/code><\/p>\n\n\n\n5<\/code><\/p>\n\n\n\n
The largest subarray with sum 0 is [-2, 2, -8, 1, 7]<\/code> (from index 1 to 5).<\/p>\n\n\n\nExample 2<\/h3>\n\n\n\n
arr = [1]<\/code><\/p>\n\n\n\n0<\/code><\/p>\n\n\n\n
There is no subarray with sum 0.<\/p>\n\n\n\nBrute Force Solution<\/h2>\n\n\n\n
Intuition and Approach<\/h3>\n\n\n\n
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For every possible starting index, check every possible ending index and calculate the sum of the subarray from start to end.<\/li>\n\n\n\n
If the sum is zero, update the maximum length found so far.<\/li>\n\n\n\n
We are checking every possible subarray, so we won\u2019t miss any that sum to zero.<\/li>\n<\/ol>\n\n\n\nCode Implementation<\/h3>\n\n\n\n