Leetcode - 933 number of recent requests

deque

class RecentCounter {
    
    private Deque<Integer> deque;
    public RecentCounter() {
    
        deque = new LinkedList<>();
    }
    
    public int ping(int t) {
    
        deque.offerLast(t);
        while(deque.size()!= 0 && t - 3000 > deque.peekFirst())
              deque.pollFirst();
        return deque.size();
    }
}

/** * Your RecentCounter object will be instantiated and called as such: * RecentCounter obj = new RecentCounter(); * int param_1 = obj.ping(t); */