21 lines
418 B
Python
21 lines
418 B
Python
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#!/usr/bin/env python3
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def primes(n):
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count = 0
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sieve = [False]*n
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for p in range(2, n):
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if sieve[p]:
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continue
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for i in range(p**2, n, p):
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sieve[i] = True
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np = 2*p
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for p2 in range(2,p+1):
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if np >= n:
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break
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if not sieve[p2]:
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count += 1
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np += p
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return count
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print(primes(10**8))
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