import collections
X = list(input())
C = collections.Counter(X)
if len(C)==1:
    print(-1)
    exit()
cnt = 0
for k,v in C.items():
    if k!='0':
        cnt+=v
if cnt==1:
    print(-1)
    exit()
for i in range(0,10):
    for j in range(i+1,10):
        if C[str(i)] and C[str(j)]:
            ans = ''
            for k in reversed(range(10)):
                ans+=str(k)*(C[str(k)]-int(k==j))
                if k==i:
                    ans+=str(j)
            print(ans)
            exit()