X = list(input())
X.sort(reverse=True)
for i in range(len(X)-1, 0, -1):
    if X[i]!=X[i-1]:
        if X[i]=="0" and i-1==0:
            continue
        X[i], X[i-1] = X[i-1], X[i]
        print("".join(X))
        exit()
print(-1)