mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 05:21:09 +00:00
7592cba417
* added sol3.py for problem_20 * added sol4.py for problem_06 * ran `black .` on `\Python`
43 lines
794 B
Python
43 lines
794 B
Python
"""
|
|
Sieve of Eratosthenes
|
|
|
|
Input : n =10
|
|
Output : 2 3 5 7
|
|
|
|
Input : n = 20
|
|
Output: 2 3 5 7 11 13 17 19
|
|
|
|
you can read in detail about this at
|
|
https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
|
|
"""
|
|
|
|
|
|
def prime_sieve_eratosthenes(num):
|
|
"""
|
|
print the prime numbers upto n
|
|
|
|
>>> prime_sieve_eratosthenes(10)
|
|
2 3 5 7
|
|
>>> prime_sieve_eratosthenes(20)
|
|
2 3 5 7 11 13 17 19
|
|
"""
|
|
|
|
primes = [True for i in range(num + 1)]
|
|
p = 2
|
|
|
|
while p * p <= num:
|
|
if primes[p] == True:
|
|
for i in range(p * p, num + 1, p):
|
|
primes[i] = False
|
|
p += 1
|
|
|
|
for prime in range(2, num + 1):
|
|
if primes[prime]:
|
|
print(prime, end=" ")
|
|
|
|
|
|
if __name__ == "__main__":
|
|
num = int(input())
|
|
|
|
prime_sieve_eratosthenes(num)
|