timeStr = input()#12:23:23timeList = timeStr.split(":")h = int(timeList[0])m = int(timeList[1])s = int(timeList[2])s += 1if s == 60: m += 1 s = 0 if m == 60: h += 1 m = 0 if h == 24: h = 0print("%.2d:%.2d:%.2d" % (h, m, s))