using pll=pair<int,int>;

class SummaryRanges {
public:

    set<pll>itv;
    set<int>added;
    void p(pll P)
    {
	    auto nx=itv.lower_bound(P);
	    --nx;auto pv=nx;nx++;
	    auto[lp,rp]=*pv;auto[ln,rn]=*nx;auto&[l,r]=P;
	    if(ln==r)r=rn,itv.erase(nx);
	    if(rp==l)l=lp,itv.erase(pv);
	    itv.insert(P);
    }

    SummaryRanges() {
        itv.emplace(-9,-9);
        itv.emplace(1e9+7,1e9+7);
    }
    
    void addNum(int value) {
        if(!added.count(value))
        {
            added.insert(value);
            p({value,value+1});
        }
    }
    
    vector<vector<int>> getIntervals() {
        vector<vector<int>>vv;
        for(auto&[i,j]:itv)if(i!=j)vv.push_back({i,j-1});
        return vv;
    }
};