МКОШП Задача I ТВ (test 1)

#include<bits/stdc++.h>
#define LINT long long int
#define ULINT unsigned long long int
using namespace std;
class Type{
 public:
     set<pair<pair<LINT, LINT>, LINT>> s;
     pair<LINT, LINT> p;
};
int main() {
    int n, m;
    cin >> n;
    vector<pair<LINT, LINT>> vc(n);
    for (auto& x : vc) {
        cin >> x.first >> x.second;
    }
    vector<Type> res(n);
    res[n - 1].p = vc[n - 1];
    res[n - 1].s.insert({vc[n - 1], n - 1});
    for (int i = n - 2; i >= 0; --i) {
        res[i].s = res[i + 1].s;
        auto it = res[i].s.lower_bound({{vc[i].second, -1}, -1});
        if (it == res[i].s.begin()) {
            if (it != res[i].s.end()) {
                if ((*it).first.first == vc[i].second) {
                    LINT t = (*it).first.second;
                    res[i].s.erase(it);
                    res[i].s.insert({{vc[i].first, t}, i});
                    res[i].p = {vc[i].first, t};
                    continue;
                }
            } else
                continue;
        } else
            it--;
        auto mn = it;
        if (!((*it).first.first <= vc[i].second && (*it).first.second >= vc[i].second)) {
            res[i].s.insert({vc[i], i});
            res[i].p = vc[i];
        } else {
            it--;
            while ((*it).first.first <= vc[i].second && (*it).first.second >= vc[i].second) {
                if ((*it).second < (*mn).second)
                    mn = it;
                if (it != res[i].s.begin())
                    it--;
                else
                    break;
            }
            LINT t = (*mn).first.second;
            res[i].s.erase(mn);
            res[i].p = {vc[i].first, t};
            res[i].s.insert({{vc[i].first, t}, i});
        }
    }
    cin >> m;
    LINT tmp1, tmp2;
    for (int i = 0; i < m; ++i) {
        cin >> tmp1 >> tmp2;
        tmp2--;
        if (res[tmp2].p.first <= tmp1 && tmp1 <= res[tmp2].p.second)
            cout << res[tmp2].p.second - tmp1 << endl;
        else {
            bool f = false;
            auto it = res[i].s.upper_bound({{vc[i].second, -1}, -1});
            it--;
            auto mn = it;
             while ((*it).first.first <= tmp1 && (*it).first.second >= tmp1) {
                f = true;
                if ((*it).second < (*mn).second)
                    mn = it;
                if (it != res[i].s.begin())
                    it--;
                else
                    break;
            }
            if (f)
                cout << (*mn).first.second - tmp1 << endl;
            else
                cout << 0 << endl;
        }
    }
}