31 lines
585 B
Python
31 lines
585 B
Python
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from sys import argv
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def binomcoeff(n,k):
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nom = 1
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denum = 1
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for i in range(n-k):
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nom *= (n-i)
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denum *= (i+1)
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v = nom//denum
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return v
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def is_prime(n):
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if n <= 1:
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return False
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for k in range(1,n):
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bc = binomcoeff(n,k)
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r = bc % n
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# print("%d %% %d = %d" % (bc,n,r))
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if r != 0:
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return False
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return True
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if len(argv) > 1:
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p = int(argv[1])
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if is_prime(p):
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print("%d is a prime" % p)
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else:
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print("%d is not a prime" % p)
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else:
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print("%s <number>" % argv[0])
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