H, M = map(int, input().split(':'))

T = (H * 60 + M + 5) % 1440

H = T // 60

M = T % 60

if H < 10:
    
    H = '0' + str(H)
    
else:
    
    H = str(H)
    
if M < 10:
    
    M = '0' + str(M)
    
else:
    
    M = str(M)
    
print(H + ':' + M)