'''
time: 12:00:00 plus 1 second
time result : 12:00:01
'''

t1 =  input("pls input the time: ")
list1 = t1.split(":")
hour = eval(list1[0])
minute = eval(list1[1])
second = eval(list1[2])
if hour > 24 or minute > 59 or second > 59 :
print("pls input the right format")
exit()
if second < 59 :
print("%d:%d:%d"%(hour,minute,second + 1))
else:
if minute < 59 :
print("%d:%d:00"%(hour,minute + 1))
else:
if hour <  23 :
print("%d:00:00"%(hour + 1))
else:
print("00:00:00")