livros.cpp

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

int main(){

    int n;
    cin >> n;

    map<int,int> m;
    vector<pair<int,int> > v;

    for(int i=0; i<n; i++){

        int x, y; cin >> x >> y;

        v.push_back({x,1});
        v.push_back({x+y, -1});
    }

    sort(v.begin(),v.end());

    int cont = 0;
    vector<int> sum(2*n+1,0);

    for(int i=0; i<2*n; i++){// compressão de coordenadas

        int x = v[i].first, y = v[i].second;

        if(m.find(x) == m.end()){

            cont ++;
            m[x] = cont;
        }

        sum[m[x]] += y;
    }

    int res = 0;

    for(int i=1; i<=cont; i++){

        sum[i] += sum[i-1];
        res = max(sum[i], res);
    }

    cout << res << endl;
}