55 lines
1.5 KiB
Python
55 lines
1.5 KiB
Python
#!/usr/bin/env python3
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# By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total from top to bottom is 23.
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#
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# 3
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# 7 4
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# 2 4 6
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# 8 5 9 3
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#
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# That is, 3 + 7 + 4 + 9 = 23.
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# Find the maximum total from top to bottom in p067_triangle.txt (right click and 'Save Link/Target As...'), a 15K text file containing a triangle
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# with one-hundred rows.
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#
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# NOTE: This is a much more difficult version of Problem 18. It is not possible to try every route to solve this problem, as there are 299 altogether!
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# If you could check one trillion (1012) routes every second it would take over twenty billion years to check them all.
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# There is an efficient algorithm to solve it. ;o)
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import sys
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from timeit import default_timer
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from projecteuler import find_max_path
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def main():
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start = default_timer()
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triang = []
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try:
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with open('p067_triangle.txt', 'r', encoding='utf-8') as fp:
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for line in fp:
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triang.append(line.strip('\n').split())
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except FileNotFoundError:
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print('Error while opening file p067_triangle.txt')
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sys.exit(1)
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l = len(triang)
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for i in range(l):
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triang[i] = list(map(int, triang[i]))
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# Use the function implemented in projecteuler.c to find the maximum path.
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max_ = find_max_path(triang, 100)
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end = default_timer()
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print('Project Euler, Problem 67')
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print(f'Answer: {max_}')
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print(f'Elapsed time: {end - start:.9f} seconds')
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if __name__ == '__main__':
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main()
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