uses crt;
var m,n,i:integer;
s:int64;
begin
clrscr;
write('m='); readln(m);
write('n='); readln(n);
if (m>0) and (n>0) then
begin
if m<n then
begin
s:=1;
for i:=m to n do
if i mod 2=0 then s:=s*i;
writeln('tich cac so chan trong khoang tu ',m,' toi ',n,' la: ',s);
end
else writeln('vui long nhap m nho hon n');
end
else writeln('vui long nhap hai so duong');
readln;
end.