from functools import lru_cache
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

S = list(input().rstrip())
N = len(S)
if N < 3:
    print(0)
    exit()

ans = 0


@lru_cache(maxsize=None)
def rec(score, bit):
    global ans
    if score > ans:
        ans = score
    for i in range(N-2):
        if (bit >> i) & 1:
            continue
        a = S[i]
        for j in range(i + 1, N - 1):
            if (bit >> j) & 1:
                continue
            b = S[j]
            for k in range(j + 1, N):
                if (bit >> k) & 1:
                    continue
                c = S[k]
                if a != "0" and b == c and a != b:
                    bit_next = bit
                    bit_next ^= (1 << i)
                    bit_next ^= (1 << j)
                    bit_next ^= (1 << k)
                    rec(score + int(a+b+c), bit_next)


rec(0, 0)
print(ans)