Number-of-Recent-Calls.cpp

#include<deque>
class RecentCounter {
    deque<int> req;
public:
    RecentCounter() {
        req={};
    }
    
    int ping(int t) {
        req.push_back(t);
        while(req.front() < t-3000) req.pop_front();
        return req.size();
    }
};

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