Problem

Given an array of integers, write a function that returns the sum of the array's elements.
Example input: [1, 2, 3, 4, 5]
Example output: 15

Solution

// Solution:

function sumArray(array) {
  let sum = 0;
  for (let i = 0; i < array.length; i++) {
    sum += array[i];
  }
  return sum;
}

// Explanation:
// This solution is optimal because it uses a for loop to iterate through the array and add each element to the sum variable.
// The for loop is the most efficient way to iterate through an array.
// The sum variable is initialized to 0 so that it can be added to.
// The sum variable is returned at the end of the function.