X = list(input())
X.sort(reverse=True)
N = len(X)
flg = True
for i in range(N-1,0,-1):
    if X[i] == X[i-1]:
        continue
    X[i],X[i-1] = X[i-1],X[i]
    flg = False
    break
if X[0] == '0' or flg:
    print(-1)
else:
    print(''.join(X))