Problem018.py

#===============================================================================
# Find the maximum total from top to bottom of the triangle below
#===============================================================================

class Node:
    def __init__(self, val, left, right):
        self.val = val
        self.left = left
        self.right = right
        self.maxpath = -1

def getMaxPath(node):
    if node == None:
        return 0
    if node.maxpath == -1:
        node.maxpath = max(getMaxPath(node.left), getMaxPath(node.right)) + node.val
    return node.maxpath

triangle = '''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'''
layers = triangle.split('\n')
grid = []

for i in range(len(layers)):
    numList = layers[i].split(' ')
    grid.append([])
    for j in range(len(numList)):
        grid[i].append(Node(int(numList[j]), None, None))
        if i - 1 >= 0:
            if j < len(grid[i - 1]):
                grid[i - 1][j].left = grid[i][j]
            if j - 1 >= 0 and j - 1 < len(grid[i - 1]):
                grid[i - 1][j - 1].right = grid[i][j]

print(getMaxPath(grid[0][0]))