S=input().split(':')

h=int(S[0])
m=int(S[1])

m=m+5

if( m >=60):
   m=m-60
   h=h+1

if(h==24):
   h=0

if(h<10):
   print(0,end='')
   print(h,end='')
   print(':',end='')
   if(m<10):
      print('0',end='')
      print(m)
   else:
      print(m)
else:
   print(h,end='')
   print(':',end='')
   if(m<10):
      print('0',end='')
      print(m)
   else:
      print(m)