39 lines
901 B
Python
39 lines
901 B
Python
#!/usr/bin/python
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# The 5-digit number, 16807=7^5, is also a fifth power. Similarly, the 9-digit number, 134217728=8^9, is a ninth power.
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#
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# How many n-digit positive integers exist which are also an nth power?
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from timeit import default_timer
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def main():
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start = default_timer()
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i = 1
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count = 0
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finished = 0
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while not finished:
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# When j=10, j^i will have i+1 digits (e.g. if i=3, 10^3=1000).
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for j in range(1, 10):
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p = j ** i
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if len(str(p)) == i:
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count = count + 1
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# When 9^i has less than i digits, all the numbers have been found.
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if len(str(p)) < i:
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finished = 1
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i = i + 1
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end = default_timer()
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print('Project Euler, Problem 63')
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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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