def henkan(moziretsu : list) -> list:
  number_list = []
  for i in moziretsu:
    try:
      number = int(i)
      number_list.append(number)
    except Exception:
      continue
  return number_list

def main():
  ans = 0
  S = input()
  S_list = list(S)
  chenged_list = henkan(S_list)
  for i in chenged_list:
    ans += i
  print(ans)

if __name__ == '__main__':
  main()