Sort Characters By Frequency
Given a string s, sort it in decreasing order based on the frequency of the characters. The frequency of a character is the number of times it appears in the string.
Return the sorted string. If there are multiple answers, return any of them.
Example 1
Input
s = "tree"Output
"eert"'e' appears twice while 'r' and 't' both appear once, so 'e' must appear before both 'r' and 't'; therefore "eetr" is also a valid answer.
Example 2
Input
s = "cccaaa"Output
"aaaccc"Both 'c' and 'a' appear three times, so both "cccaaa" and "aaaccc" are valid answers, but "cacaca" is incorrect because the same characters must be together.
Constraints
- 1 <= s.length <= 5 * 10^5
sconsists of uppercase and lowercase English letters and digits.