largestSum

largestSum.js

function sum(...nums) {
  return nums.reduce((a, b) => a + b, 0)
}

function largestSum(array) {
  let largestSumSoFar
  for (let i = 0; i < array.length; i++) {
    for (let j = i; j < array.length; j++) {
      let subArray = array.slice(i, j + 1)
      let test = sum(...subArray)
      if (typeof largestSumSoFar === 'undefined' || test > largestSumSoFar) {
        largestSumSoFar = test
      }
    }
  }
  return largestSumSoFar
}

console.log(largestSum([1, 5, -3, 4, -1, 7]))