#include <bits/stdc++.h>
using namespace std;

int maxEvents(vector<int> arrival, vector<int> duration) {
    int maxNumPresentations = 0;
    int prevArrivalTime = 0;
    [[maybe_unused]] int currentDuration = 0;
    set<int> prevDurations; // order durations.
    for (size_t i = 0; i < arrival.size(); i++)
    {
        int arrivalTime = arrival.at(i);
        int currduration = duration.at(i);
        cout << "arrivalTime: " << arrivalTime << " duration: " << currduration << endl;
        if (arrivalTime > prevArrivalTime + /*prevDurations.back()*/ *prevDurations.rbegin())
        {
            if (currduration >= /*prevDurations.back()*/ *prevDurations.rbegin())
            {
                prevArrivalTime = arrivalTime;
                prevDurations.insert(currduration);
                maxNumPresentations ++;
            }
            else if(arrivalTime == prevArrivalTime)
            {
                if (currduration > /*prevDurations.back()*/ *prevDurations.rbegin())
               {
                   maxNumPresentations++;
               }
            }
        }        
    }
    return maxNumPresentations;
}

int main()
{
    // 0100 | 0011
    cout << (4 | 3) << endl;
    cout << (4 & 3) << endl;
    cout << (4 ^ 3) << endl;
}