#!/usr/bin/python3

# 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.
#
#    3
#   7 4
#  2 4 6
# 8 5 9 3
#
# That is, 3 + 7 + 4 + 9 = 23.
# Find the maximum total from top to bottom in triangle.txt (right click and 'Save Link/Target As...'), a 15K text file containing a triangle
# with one-hundred rows.
#
# 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!
# If you could check one trillion (1012) routes every second it would take over twenty billion years to check them all.
# There is an efficient algorithm to solve it. ;o)

from timeit import default_timer
from projecteuler import find_max_path

def main():
    start = default_timer()

    try:
        fp = open('triangle.txt', 'r')
    except:
        print('Error while opening file {}'.format('triangle.txt'))
        exit(1)

    triang = list()

    for line in fp:
        triang.append(line.strip('\n').split())

    fp.close()

    l = len(triang)

    for i in range(l):
        triang[i] = list(map(int, triang[i]))

#   Use the function implemented in projecteuler.c to find the maximum path.
    max_ = find_max_path(triang, 100)

    end = default_timer()

    print('Project Euler, Problem 67')
    print('Answer: {}'.format(max_))

    print('Elapsed time: {:.9f} seconds'.format(end - start))

if __name__ == '__main__':
    main()