#!/usr/bin/env python3

from sys import argv
import csv
from time import strptime, mktime

column_no = 6
skip_rows = 11
time_format = '%Y%m%d:%H%M'

first = True
with open(argv[1]) as file_in, open(argv[2], 'w') as file_out:
  for _ in range(skip_rows):
    file_in.readline()
  writer = csv.writer(file_out, delimiter=' ')
  for row in csv.reader(file_in):
    try:
      t = mktime(strptime(row[0], time_format))
      val = row[column_no]
    except:
      break
    if first:
      t0 = t
      first = False
    writer.writerow([t - t0, val])