Given a string s containing an out-of-order English representation of digits 0-9, return the digits in ascending order.

Example 1:

Input: s = "owoztneoer"
Output: "012"

Example 2:

Input: s = "fviefuro"
Output: "45"

Constraints:

• 1 <= s.length <= 105
• s[i] is one of the characters ["e","g","f","i","h","o","n","s","r","u","t","w","v","x","z"].
• s is guaranteed to be valid.