Submission #409657

#	Time	Username	Problem	Language	Result	Execution time	Memory
409657		tempus	Strange Device (APIO19_strange_device)	C++17	5 / 100	594 ms	32452 KiB

strange_device

#include <bits/stdc++.h>

#define ll long long
#define endl "\n"
#define ios ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0);

using namespace std;

int main() {
    ios
    int n;
    cin >> n;
    ll A, B;
    cin >> A >> B;
    ll S = 0;
    map <ll, ll> was;
    ll l[n], r[n], ans = 0;
    for (int i = 0; i < n; ++ i) {
        cin >> l[i] >> r[i];
        S += r[i] - l[i] + 1;
    }
    ll cA = A;
    cA /= __gcd(B - 1, A);

    if (B > 2e18 / cA + 1) {
            S = 1 / 0;
        cout << S;
        return 0;
    }
    ll val = A * B / __gcd(B - 1, A);
    vector <pair <ll, ll> > v;
    for (int i = 0; i < n; ++ i) {
        if (l[i] + val <= r[i]) {
            cout << val;
            return 0;
        }
        ll ml = l[i] % val, mr = r[i] % val;
        if (ml <= mr) {
            v.push_back({ml, mr});
        }
        else {
            v.push_back({0, mr});
            v.push_back({ml, val - 1});
        }
    }
    sort(v.begin(), v.end());
    ans = v[0].second - v[0].first + 1;/*
    for (int i = 0; i < v.size(); ++ i) {
        cout << v[i].first << " " << v[i].second << endl;
    }+*/
    for (int i = 1; i < v.size(); ++ i) {
        ll nl = v[i].first, nr = v[i].second;
        if (nl > v[i - 1].second) {
            ans += nr - nl + 1;
            continue;
        }
        else if (nr <= v[i - 1].second) {
            v[i].second = v[i - 1].second;
        }
        else {
            ans += nr - v[i - 1].second;
        }
    }
    cout << ans;
    //3 3 3 4 4 7 9 17 18
    return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:26:19: warning: division by zero [-Wdiv-by-zero]
   26 |             S = 1 / 0;
      |                 ~~^~~
strange_device.cpp:51:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |     for (int i = 1; i < v.size(); ++ i) {
      |                     ~~^~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 0 / 5
• Subtask 5: 0 / 5
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20
• Subtask 8: 0 / 30