Number of Recent Calls
让设计一个数据结构, 给一个方法ping, 求3000ms内ping的数量.
因为只问数量, 用pq直接存数字可以求解.
class RecentCounter {
PriorityQueue<Integer> pq = new PriorityQueue<>();
public RecentCounter() {
}
public int ping(int t) {
pq.add(t);
while(pq.peek() < t - 3000){
pq.poll();
}
return pq.size();
}
}
/**
* Your RecentCounter object will be instantiated and called as such:
* RecentCounter obj = new RecentCounter();
* int param_1 = obj.ping(t);
*/