var s:array[-20..9]of string;i,j:comp;c,d:char;begin
repeat
read(c);inc(j);i:=i-ord(c>d)+ord(c<d);d:=c;str(s[i],c:j-length(s[i]),s[i])until
eoln;for i:=-20to 9do write(s[i],^j:ord(s[i]>''))end.