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import math

from typing import Generator

def slow_primes(max: int) -> Generator[int, None, None]:

"""

Return a list of all primes numbers up to max.

>>> list(slow_primes(0))

[]

>>> list(slow_primes(-1))

[]

>>> list(slow_primes(-10))

[]

>>> list(slow_primes(25))

[2, 3, 5, 7, 11, 13, 17, 19, 23]

>>> list(slow_primes(11))

[2, 3, 5, 7, 11]

>>> list(slow_primes(33))

[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31]

>>> list(slow_primes(10000))[-1]

9973

"""

numbers: Generator = (i for i in range(1, (max + 1)))

for i in (n for n in numbers if n > 1):

for j in range(2, i):

if (i % j) == 0:

break

else:

yield i

def primes(max: int) -> Generator[int, None, None]:

"""

Return a list of all primes numbers up to max.

>>> list(primes(0))

[]

>>> list(primes(-1))

[]

>>> list(primes(-10))

[]

>>> list(primes(25))

[2, 3, 5, 7, 11, 13, 17, 19, 23]

>>> list(primes(11))

[2, 3, 5, 7, 11]

>>> list(primes(33))

[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31]

>>> list(primes(10000))[-1]

9973

"""

numbers: Generator = (i for i in range(1, (max + 1)))

for i in (n for n in numbers if n > 1):

# only need to check for factors up to sqrt(i)

bound = int(math.sqrt(i)) + 1

for j in range(2, bound):

if (i % j) == 0:

break

else:

yield i

if __name__ == "__main__":

number = int(input("Calculate primes up to:\n>> ").strip())

for ret in primes(number):

print(ret)

# Let's benchmark them side-by-side...

from timeit import timeit

print(timeit("slow_primes(1_000_000)", setup="from __main__ import slow_primes"))

print(timeit("primes(1_000_000)", setup="from __main__ import primes"))

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