How to find sum of numbers in string stored in array

Question

I have figured out how to calculate the value of numbers from a single string, using as an example..

var sum = \"13-2-10-7-3\".split(\'-\').reduce(function(x, y)         


        

Answer 1

Loop over the credit card numbers and check if sum is max store it and continue to loop and store the maximum credit card number and return it:

function max_credit_sum(arr){
  max = -1
  credit_card = ''
  for(ele of arr){
    numbers = ele.replace(/-/g, '').split('')
    sum = 0
    for(num of numbers){
      sum += parseInt(num)
    }
    if(sum >= max){
      credit_card = ele
      max = sum
    }
  }
 return credit_card
}

// Test
arr = ['4916-2600-1804-0530', '4779-252888-3972', '4252-278893-7978', '4556-4242-9283-2260'] 
maximum = max_credit_sum(arr)