t=sorted(map(int,[*input()]))
for i in range(1,len(t)):
    if t[i-1]!=t[i]:
        t[i-1],t[i]=t[i],t[i-1]
        if t[::-1][0]==0:
            print(-1)
        else:
            print(''.join(map(str,t[::-1])))
        exit()
print(-1)