x = input()
li = []
for i in range(len(x)):
    li.append(x[i])

#print(li)
li.sort(reverse=True)
mx = ''.join(li)
#print(li)
li.sort()
fidx = 0
fv = li[fidx]
for i in range(1,len(x)):
    if fv != li[i]:
        tmp = li[i]
        li[i] = fv
        li[fidx] = tmp
        break
    else:
        fidx = i


li = li[::-1]
if li[0] == "0":
    print(-1)
    exit()
ans = ''.join(li)
if mx != ans:
    print(ans)
else:
    print(-1)