22 lines
648 B
Python
22 lines
648 B
Python
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def sieve_of_eratosthenes(n):
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primes = [True] * (n + 1) # 创建一个布尔列表，初始时所有元素设为True
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p = 2
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while p * p <= n:
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# 如果 primes[p] 未被标记为 False, 则是一个质数
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if primes[p]:
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# 更新所有 p 的倍数，从 p*p 开始标记为 False
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for i in range(p * p, n + 1, p):
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primes[i] = False
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p += 1
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# 收集所有质数
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prime_numbers = [p for p in range(2, n + 1) if primes[p]]
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return prime_numbers
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n=int(input())
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numbers=sieve_of_eratosthenes(n)
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for i in numbers:
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if n-i in numbers:
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print(i,n-i)
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break
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