Program vvl;
Var x:integer;
V:real;
Begin
Write('x=');
Readln (x);
V:= abs(a)-2;
Writeln ('V='; V:2:1);
End.
var n,z:longint;
begin
read(N);
z:=abs(n);
z:=z-2;
writeln(z);
end.
