var
i, n, sum: integer;
begin
writeln('Input N:');
readln(n);
sum:=0;
for i:= 2 to n do
if i mod 2 = 0 then
sum := sum + i;
writeln(sum)
end.
var
i, n, sum: integer;
begin
writeln('Input N:');
readln(n);
sum:=0;
for i:= 2 to n do
if i mod 2 = 0 then
sum := sum + i;
writeln(sum)
end.