aoc2019_14_part2.py

R,f=dict((r[-1][1],(r[-1][0],r[:-1]))for r in([(int(i),c)for i,c in map(str.split,l.replace('=>',',').split(','))]for l in open("input.txt"))),0
for b in range(40)[::-1]:
 b=1<<b;h,l={'FUEL':f+b},1
 while l:
  l=[(c,i)for c,i in h.items()if'ORE'!=c and i>0]
  for c,i in l:
   q,r=R[c];s=(i+q-1)/q;h[c]-=s*q
   for j,c in r:h[c]=h.get(c,0)+s*j
 f+=(h['ORE']<=10**12)*b
print f