Question

Given an integer n and an array a of length n, your task is to apply the following mutation to a:

Answer 1

Answer:

let a = [4, 0, 1, -2, 3];

let b = a.map( (e, i, arr) => (arr[i-1] || 0)+arr[i]+(arr[i+1] || 0) );

console.log(b);

Explanation:

The map operator is excellent for this. The || 0 operator prevents the undefined out of bounds value from ruining the result.

BTW this solution is in javascript. Other languages will presumably require more code.