Uses crt;

var st: string;

function KT (xau: string): boolean;

var i, dem: integer;

begin

dem:=0;

for i:= 1 to length(st) div 2 do

if xau<>xau[length(xau)-i+1] then

inc(dem);

if dem<>0 then

KT:=False

else

KT:=True;

end;

begin

clrscr;

write ('Nhap so co do dai khong qua 100 chu so: ');

readln (st);

if length(st)>100 then

begin

write ('Nhap khong hop le! An Enter va chay lai!');

readln;

exit;

end;

if KT(st)=True then

write ('Day la so doi xung!')

else

write ('Day la so khong doi xung!');

readln;

end.

uses crt;
var n,i,kt:longint; s:string;
begin
clrscr;
   write('n=');readln(n);
   str(n,s);
   for i:=1 to length(s) do if s[i]<>s[length(s)-i+1] then kt:=1;
   writeln(kt=0);
readln;
end.