import datetime
import sys
def next_day(date_str):
date = datetime.datetime.strptime(date_str, '%Y-%m-%d')
return (date + datetime.timedelta(days=1)).date()
def prev_day(date_str):
date = datetime.datetime.strptime(date_str,'%Y-%m-%d')
return (date - datetime.timedelta(days = 1)).date()
while True:
line = sys.stdin.readline()
line = line.strip()
if line == '':
break
print('前一天:', prev_day(line))
print('后一天:', next_day(line))
2020-04-24