n = input()

l = len(n)
if l < 3:
    print(0)
    exit()
ans = 0
Stack = []
for i in range(l - 2):
    for j in range(i + 1, l - 1):
        for k in range(j + 1, l):
            if n[i] != '0' and n[i] != n[j] and n[j] == n[k]:
                Stack.append((int(n[i] + n[j] + n[k]), n[:i] + n[i + 1:j] + n[j + 1:k] + n[k + 1:]))
if len(Stack) == 0:
    print(0)
    exit()
preStack = Stack
while preStack:
    Stack = []
    for res, nn in preStack:
        ans = max(ans, res)
        l = len(nn)
        for i in range(l - 2):
            for j in range(i + 1, l - 1):
                for k in range(j + 1, l):
                    if nn[i] != '0' and nn[i] != nn[j] and nn[j] == nn[k]:
                        Stack.append((res + int(nn[i] + nn[j] + nn[k]), nn[:i] + nn[i + 1:j] + nn[j + 1:k] + nn[k + 1:]))
    preStack = Stack
print(ans)