Submission #848257

#	Time	Username	Problem	Language	Result	Execution time	Memory
848257		popovicirobert	Strange Device (APIO19_strange_device)	C++14	100 / 100	1296 ms	100452 KiB

strange_device

#include <bits/stdc++.h>

#define lsb(x) (x & (-x))

using ull = unsigned long long;
using ll = long long;

using namespace std;

constexpr ll INF = 3e18;

int main() {
#ifdef HOME
    ifstream cin("input.in");
    ofstream cout("output.out");
#endif
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    int n;
    ll a, b;
    cin >> n >> a >> b;

    ll period;
    if (INF / b < a / __gcd(a, b + 1)) {
        period = INF;
    } else {
        period = (a / __gcd(a, b + 1)) * b;
    }

    multiset<pair<ll, ll>> mst;

    for (int i = 0; i < n; i++) {
        ll l, r;
        cin >> l >> r;

        if (r - l + 1 >= period) {
            cout << period << "\n";
            return 0;
        }

        auto Add = [&](ll l, ll r) {
            ll new_l = l, new_r = r;
            vector<pair<ll, ll>> temp;

            auto itr = mst.insert({l, r});

            auto prv = itr;
            while (prv != mst.begin() && prv->second >= l) {
                new_l = min(new_l, prv->first);
                new_r = max(new_r, prv->second);
                temp.push_back(*prv);
                prv = prev(prv);
            }
            if (prv->second >= l) {
                new_l = min(new_l, prv->first);
                new_r = max(new_r, prv->second);
                temp.push_back(*prv);
                temp.push_back(*prv);
            }

            auto nxt = itr;
            while (nxt != mst.end() && nxt->first <= r) {
                new_l = min(new_l, nxt->first);
                new_r = max(new_r, nxt->second);
                temp.push_back(*nxt);
                nxt = next(nxt);
            }

            for (auto s : temp) {
                mst.erase(s);
            }

            mst.insert({new_l, new_r});
        };

        l %= period;
        r %= period;

        if (l > r) {
            Add(l, period - 1);
            Add(0, r);
        } else {
            Add(l, r);
        }
    }

    ll answer = 0;
    for (auto itr : mst) {
        answer += itr.second - itr.first + 1;
    }

    cout << answer;

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30