Submission #1342308

#	Time	Username	Problem	Language	Result	Execution time	Memory
1342308		orgiloogii	Strange Device (APIO19_strange_device)	C++20	100 / 100	345 ms	32580 KiB

strange_device

#include <bits/stdc++.h>
#define int long long
#define ff first
#define ss second
using namespace std;
signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    int n, a, b;
    cin >> n >> a >> b;
    __int128 loops = (a / __gcd(a, b + 1));
    loops *= b;
    int l[n], r[n];
    for (int i = 0;i < n;i++) {
        cin >> l[i] >> r[i];
    }
    int lim = r[n - 1];
    if (loops > lim) {
        int ans = 0;
        for (int i = 0;i < n;i++) {
            ans += r[i] - l[i] + 1;
        }
        cout << ans << endl;
        return 0;
    }
    int loop = (a / __gcd(a, b + 1));
    loop *= b;
    vector <pair <int, int>> v;
    for (int i = 0;i < n;i++) {
        int diff = l[i] % loop;
        diff = (l[i] - diff) / loop;
        l[i] %= loop;
        // cout << l[i] << ' ' << diff << endl;
        r[i] -= diff * loop;
        if (l[i] + loop <= r[i]) {
            cout << loop;
            return 0;
        }
        if (r[i] >= loop) {
            v.push_back({0, r[i] % loop});
            v.push_back({l[i], loop - 1});
        }
        else {
            v.push_back({l[i], r[i]});
        }
    }
    sort(v.begin(), v.end());
    int ans = 0;
    int ls = -1;
    for (auto [x, y] : v) {
        if (ls >= y) {
            continue;
        }
        if (x > ls) {
            ans += y - x + 1;
        }
        else {
            ans += y - ls;
        }
        ls = max(ls, y);
    }
    cout << ans << endl;
}

• 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