Maximum path sum I and II 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.

problem18_euler.py

a = []

def getTriangleFromFile():
  f = open("triangle.txt")
  for line in f:
    b = [int(x) for x in line.split()]
    a.append(b)

maxPaths = dict()

def getMaxPathLength(x,y):
  if y < 0:
    return 0
  if x >= len(a[-1]):
    return 0
  if (x,y) in maxPaths:
    return maxPaths[x,y]
  maxPaths[x,y] = a[x][y] + max(getMaxPathLength(x+1, y +1), getMaxPathLength(x+1,y))
  return maxPaths[x,y]

getTriangleFromFile()
print getMaxPathLength(0,0)

print maxPaths