x=input()
t=sorted(x,reverse=True)
for i in range(len(t) - 2, -1, -1):
    if t[i] != t[len(t) - 1]:
        t[i],t[i+1]=t[i+1],t[i]
        break
xx=''.join(t)
if xx[0]=='0':
    print('-1')
elif xx!=x:
    print(''.join(t))
else:
    print('-1')