Submission #1016320

#	Time	Username	Problem	Language	Result	Execution time	Memory
1016320		VMaksimoski008	Strange Device (APIO19_strange_device)	C++17	100 / 100	325 ms	53960 KiB

strange_device

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

const int mod = 1e9 + 7;

int main() {
    ios_base::sync_with_stdio(false);
    cout.tie(0); cin.tie(0);
    
    ll n, A, B;
    cin >> n >> A >> B;

    ll P = min( (__int128_t)A / (__int128_t)__gcd(A, B + 1) * (__int128_t)B, (__int128_t)1e18 + 1 );

    vector<pair<ll, ll> > st;
    for(int i=0; i<n; i++) {
        ll L, R;
        cin >> L >> R;

        if(R - L + 1 >= P) {
            cout << P << '\n';
            return 0;
        }
        
        ll a = L % P, b = R % P;
        if(L == R) {
            st.push_back({ a, b });
        } else if(a < b) {
            st.push_back({ a, b });
        } else {
            st.push_back({ a, P - 1 });
            st.push_back({ 0, b });
        }
    }

    ll res = 0;
    sort(st.begin(), st.end());
    ll left_end=st[0].first, right_end=st[0].second;
    for(int i=1; i<st.size(); i++) {
        if(st[i].first > right_end) {
            res += right_end - left_end + 1;
            left_end = st[i].first;
            right_end = st[i].second;
        } else {
            right_end = max(right_end, st[i].second);
        }
    }

    cout << res + right_end - left_end + 1 << '\n';
    return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:40:19: 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]
   40 |     for(int i=1; i<st.size(); i++) {
      |                  ~^~~~~~~~~~

• 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