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19 lines
844 B
Python
19 lines
844 B
Python
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'''
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-The sieve of Eratosthenes is an algorithm used to find prime numbers, less than or equal to a given value.
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-Illustration: https://upload.wikimedia.org/wikipedia/commons/b/b9/Sieve_of_Eratosthenes_animation.gif
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'''
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from math import sqrt
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def SOE(n):
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check = round(sqrt(n)) #Need not check for multiples past the square root of n
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sieve = [False if i <2 else True for i in range(n+1)] #Set every index to False except for index 0 and 1
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for i in range(2, check):
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if(sieve[i] == True): #If i is a prime
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for j in range(i+i, n+1, i): #Step through the list in increments of i(the multiples of the prime)
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sieve[j] = False #Sets every multiple of i to False
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for i in range(n+1):
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if(sieve[i] == True):
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print(i, end=" ")
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