# Open the input file
with open("input.txt", "r") as input_file:
  # Initialize the maximum number of calories
  max_calories = 0

  # Read the input
  total_calories = 0
  for line in input_file:
    line = line.strip()
    if line == "":
      # Empty line, update the maximum number of calories
      max_calories = max(max_calories, total_calories)
      total_calories = 0
    else:
      # Non-empty line, add the number of calories to the current total
      total_calories += int(line)

  # Add the last Elf's calories to the maximum (if any)
  max_calories = max(max_calories, total_calories)

  # Print the result
  print(max_calories)