Submission #1239481

#	Time	Username	Problem	Language	Result	Execution time	Memory
1239481		AksLolCoding	Strange Device (APIO19_strange_device)	C++17	100 / 100	600 ms	63080 KiB

strange_device

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

void solve() {
    ll n, a, b;
    cin >> n >> a >> b;
    __uint128_t G = __uint128_t(a) / gcd(a, b+1) * b;

    map<ll, int> m;
    while (n--) {
        ll l, r;
        cin >> l >> r;
        ll s = r - l + 1;
        // full area
        if (s >= G) {
            m[0]++;
            m[G]--;
            continue;
        }
        m[l % G]++;
        m[r % G + 1]--;
        
        // wrap around
        if ((l % G) > (r % G)) {
            m[0]++;
            m[G]--;
        }
    }

    // ans
    int sm = 0;
    ll ans = 0;
    pair<ll, int> prev = {-1, 0};
    for (auto& i: m) {
        if (prev.first == -1) {
            prev = i;
            continue;
        }
        sm += prev.second;
        if (sm > 0) {
            ans += i.first - prev.first;
        }
        prev = i;
    }

    cout << ans << '\n';
}

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    solve();
}

• 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