var s:string;    
    c:byte;    
    b:boolean;    
begin    
     readln(s);    
     b:=true;    
     while b do    
      begin    
       b:=false;    
       c:=pos('[]',s);    
       if c>0 then    
        begin    
         delete(s,c,2);    
         b:=true;    
        end;    
       c:=pos('()',s);    
       if c>0 then    
        begin    
         delete(s,c,2);    
         b:=true;    
        end;    
       c:=pos('{}',s);    
       if c>0 then    
        begin    
         delete(s,c,2);    
         b:=true;    
        end;    
      end;    
    if length(s)>0 then writeln('No')    
    else writeln('Yes');    
end.

type
  s=str[80];
  yk=^el;
  el=record
   inf:byte;
   adr:yk;
     end;
var  
  str:s;
  p:integer;
  na:yk;
const
  otkr:s=['(','[','{'];
  zakr:s=[')',']','}'];
function poisk(str[k]:char):integer;
procedure vkl(nom:byte);
...
begin
  writeln('vvedite stroku');
  readln(str);
  k:=1;
  while k<=streln(str) do
       begin
         p:=poisk(str[k]);
         if p<>0 then
                     if p>0 then vkl(p)
                     else
                         begin
                           os=izwl;
                           if os=o then writeln (...);
                           if os<>-p then writeln ('ne ta otkr.skobka');
                         end;
       inc(k);
       end;
  if izwl <>0 then writeln ('lishnie skobki');
end.