N = list(input())
N = list(map(int, N))
M = len(N)
M2 = 1 << M
dp = [0] * M2
for i in range(M2):
    for a in range(M):
        for b in range(a + 1, M):
            for c in range(b + 1, M):
                if (i >> a) & 1:
                    continue
                if (i >> b) & 1:
                    continue
                if (i >> c) & 1:
                    continue
                if N[a] == 0:
                    continue
                if N[b] != N[c]:
                    continue
                if N[a] == N[b]:
                    continue
                ni = i
                ni |= 1 << a
                ni |= 1 << b
                ni |= 1 << c
                v = int(N[a]*100 + N[b]*10 + N[c])
                dp[ni] = max(dp[ni], dp[i] + v)
print(dp[-1])