program f;<br />
var s,snew:string;<br />
i,n:byte;<br />
begin<br />
write('vv stroky');<br />
readln(s);<br />
n:=length(s);<br />
snew:=s[1];<br />
for i:=2 to n do<br />
if s[i]<>s[i-1] then snew:=snew+s[i];<br />
writeln(snew);<br />
end.