#!/usr/bin/env python3 import re NUM = 9 lines = (x for x in open("input.txt")) stacks = [[] for _ in range(NUM)] for line in lines: if '[' not in line: break for i, v in enumerate(line[1::4]): if v != ' ': stacks[i].append(v) next(lines) for line in lines: a, s, t = map(int, re.search(r"move (\d+) from (\d+) to (\d+)", line).groups()) stacks[t-1] = stacks[s-1][:a][::-1]+stacks[t-1] stacks[s-1] = stacks[s-1][a:] print(''.join(i[0] for i in stacks))