Daniele Fucini
6b29655330
Added solutions for problems 21, 22, 23, 24 and 25 both in C and in python
52 lines
1015 B
Python
52 lines
1015 B
Python
#!/usr/bin/python3
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import math
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from timeit import default_timer
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def is_abundant(n):
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limit = math.floor(math.sqrt(n)) + 1
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sum_ = 1
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for i in range(2, limit):
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if n % i == 0:
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sum_ = sum_ + i
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if n != i * i:
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sum_ = sum_ + n // i
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return sum_ > n
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def main():
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start = default_timer()
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ab_nums = [False] * 28124
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for i in range(12, 28124):
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ab_nums[i] = is_abundant(i)
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sums = [False] * 28124
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for i in range(1, 28123):
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if ab_nums[i]:
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for j in range(i, 28123):
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if ab_nums[j]:
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sum_ = i + j
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if sum_ <= 28123:
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sums[sum_] = True
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sum_ = 0
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for i in range(1, 28124):
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if not sums[i]:
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sum_ = sum_ + i
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end = default_timer()
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print('Project Euler, Problem 23')
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print('Answer: {}'.format(sum_))
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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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