# (ΦωΦ)＜超いい問題だ！
var n = stdin.readLine

proc conv(c: char): int = result = int(c) - int('0')

for i in 0.. n.high:
  var ha = 0
  var p = -1
  for j in i+1.. n.high:
    var x = conv(n[j])
    if ha <= x:
      p = j
      ha = x
  if conv(n[i]) < ha:
    swap n[p], n[i]
    break
echo n