dic = dict()
for x in input():
    i = int(x)
    if i not in dic: dic[i] = 1
    else: dic[i] += 1

lst = list()
for i in range(10):
    if i in dic: lst.append((i, dic[i]))

ans = ""
while len(lst) > 2:
    k, v = lst.pop()
    ans += str(k) * v

if len(lst) == 2:
    k1, v1 = lst.pop()
    ans += str(k1) * (v1 - 1)

    k0, v0 = lst.pop()
    ans += str(k0) + str(k1)
    ans += str(k0) * (v0 - 1)

if ans == "" or ans[0] == "0": ans = -1
print(ans)