var
S: real;
i, k, l: integer;
begin
S := 1;
for i := 1 to 12 do
begin
k := 1; l := 1;
while (k <= i) do<br> begin
l := l * 3;
k := k + 1;
end;
S := S + 1 / l;
end;
writeln(S);
end.
-------------
function len(s: integer): byte;
var
i, l: byte;
begin
l := s;
while (l > 0) do
begin
l := l div 10;
inc(i);
end;
len := i;
end;
var
i: integer;
begin
i := 3;
repeat
i := i * 3;
until (len(i) = 6);
writeln(i);
end.
---------------
var
D, x: real;
y: integer;
begin
readln(x);
if (x > 0) then
for y := 1 to 5 do
D := D + (y + cos(x))
else
begin
D := 1;
while (y <= 10) do<br> begin
D := D * (y - x);
inc(y);
end;
end;
writeln('D = ', D);
end.