var
x:longint;
flag: boolean;
begin
read(x);
flag := false;
if (x mod 4 = 0) and (x mod 100 <> 0) then flag := true;
if x mod 400 = 0 then flag := true;
if flag then writeln(‘leap year!’)
else writeln(‘not a leap year!’);
end.

输入:1234
输出
输出：not a leap year!