Day 9: Disk Fragmenter
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python
solution
import aoc
def setup():
dm = [int(x) for x in aoc.get_lines(9, stripped=True)[0]]
ldm = len(dm)
d = []
f = 0
for i in range(0, ldm, 2):
lfi = dm[i]
d.extend([f] * lfi)
f += 1
if i + 1 < ldm:
lfr = dm[i + 1]
d.extend([-1] * lfr)
return d
def one():
d = setup()
h = 0
t = len(d) - 1
while h < t:
if d[h] == -1:
while t > h and d[t] == -1:
t -= 1
if t > h:
d[h], d[t] = d[t], d[h]
t -= 1
h += 1
print(sum(i * v for i, v in enumerate(d) if v != -1))
def two():
d = setup()
md = max(d)
for fid in range(md, -1, -1):
fis = [i for i, v in enumerate(d) if v == fid]
if not fis:
continue
s, e = fis[0], fis[-1] + 1
l, f, fi = e - s, 0, None
for i in range(s):
if d[i] == -1:
if f == 0:
fi = i
f += 1
if f == l:
break
else:
f, fi = 0, None
if fi is not None and f == l:
d[fi:fi+l] = [fid]*l
d[s:e] = [-1]*l
print(sum(i * v for i, v in enumerate(d) if v != -1))
one()
two()
