uses crt;
var e,t,s:real;
n:integer;
begin
clrscr;
e:=0.001;
n:=1;
t:=2;
s:=1/2;
while abs(2*n-1)/t>e do
begin
n:=n+1;
t:=t*2;
s:=s+(2*n-1)/t;
end;
write('S=',s:0:4);
readln
end.
uses crt;
var e,t,s:real;
n:integer;
begin
clrscr;
e:=0.001;
n:=1;
t:=2;
s:=1/2;
while abs(2*n-1)/t>e do
begin
n:=n+1;
t:=t*2;
s:=s+(2*n-1)/t;
end;
write('S=',s:0:4);
readln
end.