18.py

"""
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 of the triangle below:

NOTE: As there are only 16384 routes, it is possible to solve this problem
 by trying every route. However, Problem 67, is the same challenge with a
 triangle containing one-hundred rows; it cannot be solved by brute force,
 and requires a clever method! ;o)
"""
triangle_data = """
75
95 64
17 47 82
18 35 87 10
20 04 82 47 65
19 01 23 75 03 34
88 02 77 73 07 63 67
99 65 04 28 06 16 70 92
41 41 26 56 83 40 80 70 33
41 48 72 33 47 32 37 16 94 29
53 71 44 65 25 43 91 52 97 51 14
70 11 33 28 77 73 17 78 39 68 17 57
91 71 52 38 17 14 91 43 58 50 27 29 48
63 66 04 68 89 53 67 30 73 16 69 87 40 31
04 62 98 27 23 09 70 98 73 93 38 53 60 04 23
"""


def main():
    print(solve())


def solve():
    triangle_nums = [row.split(" ") for row
                     in triangle_data.strip().split("\n")]
    triangle = [[int(el) for el in row] for row in triangle_nums]
    return recur_add_row(0, 0, 0, triangle)


def recur_add_row(row, column, sum, triangle):
    if row > 14:
        return sum
    else:
        return max(
            recur_add_row(row + 1, column,
                          sum + triangle[row][column], triangle),
            recur_add_row(row + 1, column + 1,
                          sum + triangle[row][column], triangle))


if __name__ == "__main__":
    main()