<gh_stars>0
triangle = [
    [75],
    [95,64],
    [17,47,82],
    [18,35,87,10],
    [20, 4,82,47,65],
    [19, 1,23,75, 3,34],
    [88, 2,77,73, 7,63,67],
    [99,65, 4,28, 6,16,70,92],
    [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, 4,68,89,53,67,30,73,16,69,87,40,31],
    [ 4,62,98,27,23, 9,70,98,73,93,38,53,60, 4,23]
]

prev_row = triangle[-1]
rows = list(reversed(triangle[:-1]))

for row in rows:
    for idx, val in enumerate(row):
        row[idx] = val + max(prev_row[idx], prev_row[idx+1])
    prev_row = row

print(rows[-1])
triangle = [
    [75],
    [95,64],
    [17,47,82],
    [18,35,87,10],
    [20, 4,82,47,65],
    [19, 1,23,75, 3,34],
    [88, 2,77,73, 7,63,67],
    [99,65, 4,28, 6,16,70,92],
    [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, 4,68,89,53,67,30,73,16,69,87,40,31],
    [ 4,62,98,27,23, 9,70,98,73,93,38,53,60, 4,23]
]

prev_row = triangle[-1]
rows = list(reversed(triangle[:-1]))

for row in rows:
    for idx, val in enumerate(row):
        row[idx] = val + max(prev_row[idx], prev_row[idx+1])
    prev_row = row

print(rows[-1])