Count the frequency of letters in string and arrange them into acceding order.

Question

use any language that is comfortable for you.
eg:-
string is: hey there
frequency:
e-3
h-2
y-1
t-1
r-1
new ordered string: eeehhrty

Answer 1

Haskell:

main = print . reverse . concat . sortBy (comparing length) . group . sort $ "hey there"

https://tio.run/##TYs7CsMwEAV7neJhXNiNb5DGpDT4DIuySCL6sdoEfHpFgRTpHvNmPLUnx9h7SLWI4k5K2xGamn9wysOYRCHjhiohKzYIv1kaj2VLtvRFbQT7hcWWVGloDpGzU7@Oz0l51Z@DGZPnC@pZeOr9Aw