# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	T = list(input().split(":"))
	h = int(T[0])
	m = int(T[1])
	time = 60 * h + m + 5
	time %= (60 * 24)

	hh = time // 60
	mm = time % 60
	if hh < 10:
		ansh = "0" + str(hh)
	else:
		ansh = str(hh)

	if mm < 10:
		ansm = "0" + str(mm)
	else:
		ansm = str(mm)

	print(ansh + ":" + ansm)



if __name__ == '__main__':
	main()