50 lines
887 B
Python
50 lines
887 B
Python
#!/usr/bin/python3
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from timeit import default_timer
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from projecteuler import sieve
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def is_circular_prime(n):
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global primes
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if primes[n] == 0:
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return 0
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tmp = n
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count = 0
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while tmp > 0:
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if tmp % 2 == 0:
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return 0
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count = count + 1
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tmp = tmp // 10
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for i in range(1, count):
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n = n % (10 ** (count - 1)) * 10 + n // (10 ** (count - 1))
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if primes[n] == 0:
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return 0
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return 1
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def main():
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start = default_timer()
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global primes
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primes = sieve(1000000)
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count = 13
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for i in range(101, 1000000, 2):
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if is_circular_prime(i):
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count = count + 1
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end = default_timer()
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print('Project Euler, Problem 35')
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print('Answer: {}'.format(count))
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print('Elapsed time: {:.9f} seconds'.format(end - start))
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if __name__ == '__main__':
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main()
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