X = sorted(input(), reverse=True)
if X[0] == X[-1] or X[1] == "0":
    print(-1)
else:
    for i in reversed(range(1, len(X))):
        if X[i] != X[i - 1]:
            X[i], X[i - 1] = X[i - 1], X[i]
            print("".join(X))
            quit()