input: def fibonacci(n: int):
      """Print the Fibonacci series up to a given number.
      >>> fibonacci(10)
      34
      >>> fibonacci(5)
      3
      >>> fibonacci(-1)
      Incorrect input
      """
output:     if n < 0:
          return "Incorrect input"
      if n == 0:
          return 0
      if n == 1:
          return 1
      a, b = 0, 1
      for _ in range(2, n + 1):
          a, b = b, a + b
      return b