Program Pr1;uses crt;var i,n,y:integer;Beginclrscr;y:=1;readln(n);if n>=2 then for i:=2 to n do y:=y*((i*2)-1);writeln(y);end.
Program Pr1;
uses crt;
var i,n,y:integer;
Begin
clrscr;
y:=1;
readln(n);
if n>=2 then for i:=2 to n do y:=y*((i*2)-1);
writeln(y);
end.