N = input()
d = len(N)

ret = [-1] * d

now = 0
while now < d and N[now] in "45":
    now += 1

if now == d:
    print(N)
    exit()

if now == 0:
    if N[now] in "6789":
        print("5" * d)
        exit()
    else:
        print("5" * (d - 1))
        exit()

if N[now] in "6789":
    rest = False
else:
    rest = True

for i in range(now, d):
    ret[i] = "5"

while now > 0:
    now -= 1
    if rest:
        if N[now] == "5":
            ret[now] = "4"
            rest = False
        elif now > 0:
            ret[now] = "5"
    else:
        ret[now] = N[now]

print("".join(ret))