Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Maximum subarray sum in circular array using JavaScript
Problem
We are required to write a JavaScript function that takes in an array of integers, arr, as the first and the only argument.
We can consider this array arr to be a circular array, which means the last element of the array will be followed by the first. Our function should find and return the maximum possible sum of a non-empty subarray of arr.
For example, if the input to the function is
Input
const arr = [2, -2, 3, -1];
Output
const output = 4;
Output Explanation
Because the desired subarray is [3, -1, 2]
Example
const arr = [2, -2, 3, -1];
const maxSubarraySumCircular = (arr = []) => {
let max = arr[0]
let min = arr[0]
let currentMax = max
let currentMin = min
let sum = arr[0]
for (let i = 1; i < arr.length; i++) {
currentMax = arr[i] + Math.max(currentMax, 0)
max = Math.max(max, currentMax)
currentMin = arr[i] + Math.min(currentMin, 0)
min = Math.min(min, currentMin)
sum += arr[i]
}
return max < 0 ? max : Math.max(max, sum - min)
}
console.log(maxSubarraySumCircular(arr));Output
4
Updated on: 23-Apr-2021
142 Views
Advertisements