local s = io.read()
local n = #s
local t = {}
for i = 1, n do
  t[i] = tonumber(s:sub(i, i))
end
table.sort(t, function(a, b) return a > b end)
if t[2] == 0 or t[1] == t[n] then
  print(-1)
else
  for i = n, 2, -1 do
    if t[i] ~= t[i - 1] then
      t[i], t[i - 1] = t[i - 1], t[i]
      break
    end
  end
  print(table.concat(t))
end