Leetcode-933 Number of Recent Calls(最近的请求次数)

class RecentCounter
{
    private:
        queue<int> q;
    public:
        RecentCounter()
        {
        }

        int ping(int t)
        {
            if(q.empty())
            {
                q.push(t);
                return 1;
            }
            if(t-q.front()<=3000)
            {
                q.push(t);
            }
            else
            {
                q.pop();
                while(!q.empty() && t-q.front()>3000)
                {
                    q.pop();
                }
                if(q.empty())
                {
                    q.push(t);
                    return 1;
                }
                q.push(t);
            }
            return q.size();
        }
};