autre py sans classe

ou old school :)

def solve(StacksList, lines, step=1):
 for CranesCount, StackStart, StackDest in lines:
 StacksList[StackDest] += StacksList[StackStart][-CranesCount:][::step]
 StacksList[StackStart] = StacksList[StackStart][:-CranesCount]
 return "".join(s[-1] for s in StacksList)
data, lines = open("./input").read().split("\n\n")
StacksList = [
 "".join(column).rstrip()
 for i, column in enumerate(zip(*data.splitlines()[-2::-1]))
 if i % 4 == 1
]
lines = [
 (int(line[1]), int(line[3]) - 1, int(line[5]) - 1)
 for line in map(str.split, lines.splitlines())
]
print(solve(StacksList.copy(), lines, -1))
print(solve(StacksList.copy(), lines))

pas classieux mais ça a fait le job.

"It is seldom that liberty of any kind is lost all at once." ― David Hume