import json
import sys
import datetime

def eprint(*args, **kwargs):
    print(*args, file=sys.stderr, **kwargs)

files = {}

for line in sys.stdin:
  l = json.loads(line)
  try:
    year= datetime.datetime.fromtimestamp(abs(int(l.get('date') or l['postDate']))).year
    if year < 2001 or year > 2020:
      year = "unknown"
    year = str(year)
  except:
    year = "unknown"
  file = files.get(year)
  if not file:
    file = open(f'{year}.jsonl', "w")
    files[year] = file
  file.write(line)

for f in files.values():
  f.close()