import sys
sys.set_int_max_str_digits(0)

N = str(input())

while (int(N) % 3 == 0 or '3' in N):
    i = N.find('3')
    if (i == -1):
        N = str(int(N) - 1)
    else:
        a = list(N)
        a[i] = '2'
        i += 1
        while (i < len(N)):
            a[i] = '9'
            i += 1
        N = "".join(a)
print(N)