program func;
uses crt;
var
x,y1:real;
function y (x:real):real;
begin
y:=1-x+sin(x)-ln(1+x);
end;
begin
read(x);
if x<0 then writeln('error')
else begin
     y1:=y(x);
     writeln('f(x)= ',y1);
     end;
readkey;
end.