GACHO PASCAL

var d,m,x1,x2:longint;

procedure giai;
begin
    for x1:=0 to m div 2 do
    begin
        x2:=(m-x1*2) div 4;
        if (m-x1*2) mod 4 = 0 then inc(d);
    end;
    write(d);
end;

begin
    assign(input,'gacho.inp');reset(input);
    assign(output,'gacho.out');rewrite(output);
    read(m);
    giai;
    close(input);close(output);
end.