x=list(input())
x.sort(reverse=True)
n=len(x)
if len(set(x))==1:
    print(-1)
    exit()
if x.count('0')==n-1:
    print(-1)
    exit()
for i in range(n-1,0,-1):
    if x[i]!=x[i-1]:
        x[i],x[i-1]=x[i-1],x[i]
        break
print(''.join(x))