input: def split_equal_sum(arr):
      """
      Write a function that splits a given array into two parts with equal sum.
      >>> split_equal_sum([1, 2, 3, 4])
      True
      >>> split_equal_sum([1, 2, 3, 5])
      False
      """
output:     total_sum = sum(arr)
      if total_sum % 2 != 0:
          return False
      
      target_sum = total_sum // 2
      current_sum = 0
      
      for num in arr:
          current_sum += num
          if current_sum == target_sum:
              return True
          elif current_sum > target_sum:
              return False
      
      return False