import csv, sys

outf = csv.writer(sys.stdout) 
last_row = None
outf.writerow(["url", "start", "end", "text"])
for row in csv.DictReader(sys.stdin):
    if last_row is not None:
        if last_row['url'] == row['url']:
            outf.writerow([last_row['url'], last_row['start'], row['start'], last_row['text']])
        else:
            outf.writerow([last_row['url'], last_row['start'], None, last_row['text']])
    last_row = row

outf.writerow([last_row['url'], last_row['start'], None, last_row['text']])