largestPairSumInArray.js

/* 

Given a sequence of numbers, find the largest pair sum in the sequence.

For example

[10, 14, 2, 23, 19] -->  42 (= 23 + 19)
[99, 2, 2, 23, 19]  --> 122 (= 99 + 23)
Input sequence contains minimum two elements and every element is an integer.

*/

function largestPairSum(numbers) {
  numbers.sort((a, b) => a - b).reverse();
  return numbers[0] + numbers[1];
}