How to Find the Largest Sum in a JavaScript Array of Arrays?

To find the largest sum in a JavaScript array of arrays, you can loop through each sub-array, sum its elements, and keep track of the largest sum so far:

var arrays = [[1, 2, 3], [4, 5, 6], [7, 8, 9]];
var largestSum = Number.NEGATIVE_INFINITY;

for (var i = 0; i < arrays.length; i++) {
  var currentArray = arrays[i];
  var currentSum = 0;

  for (var j = 0; j < currentArray.length; j++) {
    currentSum += currentArray[j];
  }

  if (currentSum > largestSum) {
    largestSum = currentSum;
  }
}

console.log(largestSum); // Output: 45

In this example, largestSum is a variable that keeps track of the largest sum found so far. The outer loop iterates through each sub-array in the arrays array, and the inner loop sums the elements of the current sub-array. The if statement checks whether the current sum is greater than the largest sum found so far, and updates largestSum if it is.