class Solution {
public:
    vector<vector<int>> getSkyline(vector<vector<int>>& buildings) {
        vector<pair<int, int>> evs;
        for (auto &v: buildings) {
            evs.emplace_back(v[0], v[2]);
            evs.emplace_back(v[1], -v[2]);
        }
        sort(evs.begin(), evs.end());
        multiset<int> hs = {0};
        vector<pair<int, int>> pts;
        for (auto &[x, h]: evs) {
            if (h > 0) hs.insert(h);
            else  hs.erase(hs.lower_bound(-h));
            pts.emplace_back(x, *hs.rbegin());
        }
        reverse(pts.begin(), pts.end());
        pts.erase(unique(pts.begin(), pts.end(), [](auto a, auto b) { return a.first == b.first; }), pts.end());
        reverse(pts.begin(), pts.end());
        pts.erase(unique(pts.begin(), pts.end(), [](auto a, auto b) { return a.second == b.second;}), pts.end());
        vector<vector<int>> formatted;
        for (auto &[x, h]: pts)
            formatted.push_back({x, h});
        return formatted;
    }
};