Overview

Implement fill(array, value, start, end) that fills array from start to end (exclusive) with value. Modifies and returns the original array.

Examples

fill([1,2,3,4], '*', 1, 3); // [1,'*','*',4]
fill([1,2,3], 0); // [0,0,0]

Solution

function fill(array, value, start, end) {
  const s = start ?? 0;
  const e = end ?? array.length;
  for (let i = s; i < e; i++) array[i] = value;
  return array;
}