include [HTML_REMOVED]

include [HTML_REMOVED]

include [HTML_REMOVED]

include [HTML_REMOVED]

include [HTML_REMOVED]

using namespace std;
int main(){
queue[HTML_REMOVED] q;
for(int i = 2;i < 10; i ++) q.push(i);
cout<<q.front()<<endl;
q.pop();
q.push(100);
cout<<q.front()<<endl;
cout<<q.size()<<endl;
cout<<q.back()<<endl;

if(!q.empty()) puts("not empty");
q = queue<int>();
if(q.empty()) puts("is empty");

return 0;

}