:"? :For(X,1+int(log(N)),1,-1 :Ans+sub("0123456789",1+int(10fpart(N/10^X)),1 :End :sub(Ans,1,length(Ans)-1→Str1
Not sure if this deserved a place in the wiki or not, the advantage(at least in my case) is that the numbers are appended instead of prepended to the starting string. If you need your strings to be prepended with some text you can replace the "?" with that text and remove the last line.