Submission #135477

#	Time	Username	Problem	Language	Result	Execution time	Memory
135477		Juney	Strange Device (APIO19_strange_device)	C++14	100 / 100	687 ms	18708 KiB

strange_device

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

typedef long long ll;
typedef pair<ll, ll> pll;

const ll INF = 1e18;

ll N, A, B, T;

ll sweep(vector<pll> &v) {
    ll l = 0, r = -1, ret = 0;
    for(auto line : v) {
        if(r >= line.first) r = max(r, line.second);
        else {
            ret += (r - l + 1);
            l = line.first, r = line.second;
        }
    }
    return ret + (r - l + 1);
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> N >> A >> B;
    T = A / __gcd(A, B+1);
    if(INF / A + 1 < B) T = INF;
    else T *= B, T = min(T, INF);

    vector<pll> line;
    for(int i=1; i<=N; i++) {
        ll a, b; cin >> a >> b;
        if(b - a >= T) {
            cout << T;
            return 0;
        }
        a %= T; b %= T;
        if(a > b) {
            line.push_back(pll(a, T-1));
            line.push_back(pll(0, b));
        }
        else line.push_back(pll(a, b));
    }
    sort(line.begin(), line.end());
    line.erase(unique(line.begin(), line.end()), line.end());
    cout << sweep(line);
}

• 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