X = list(input())
X.sort(reverse=True)
N = len(X)
cn = len(set(X))
if cn == 1:
    print(-1)
    exit()
if X.count('0') == N-1:
    print(-1)
    exit()
for i in range(N-1,0,-1):
    if X[i] != X[i-1]:
        X[i],X[i-1] = X[i-1],X[i]
        break
print(*X,sep='')