T = input()
 
a, b = map(int, T.split(':'))



c = b + 5
k = c % 60

if k <= 9:
    k = '0' + str(k)


    
if c >= 60:
    a = a + 1

if a <= 9:
    a = '0' + str(a)

if a == 24:
    a = '00'


s = str(a) + ':' + str(k)

print(s)