input: Write a function to find the maximum sum of an array of non-negative integers, given an upper limit value. If the given array is empty then return 0.
  assert findMaxSum(10, [1, 3, 5, 4, 2, 6])==9
  assert findMaxSum(10, [2, 3, 7, 1, 4, 4])==10
  assert findMaxSum(5, [5, 5, 5, 5])==5
  assert findMaxSum(10, [])==0
  assert findMaxSum(5, [1, 2, 3])==6
output: def findMaxSum(limit, arr):
      if not arr:
          return 0
      arr.sort(reverse=True)
      current_sum = 0
      for num in arr:
          if current_sum + num <= limit:
              current_sum += num
          if current_sum == limit:
              break
      return current_sum