Submission #1070809

#	Time	Username	Problem	Language	Result	Execution time	Memory
1070809		MohamedFaresNebili	Closing Time (IOI23_closing)	C++17	0 / 100	1034 ms	43324 KiB

closing

#include <bits/stdc++.h>
#include "closing.h"

        using namespace std;

        vector<pair<int, long long>> adj[200005];
        long long D[200005][2];
        vector<long long> pL, pR, pM;
        void dfs(int X, int p, int st) {
            for(auto u : adj[X]) {
                if(u.first == p) continue;
                D[u.first][st] = D[X][st] + u.second;
                dfs(u.first, X, st);
            }
        }
        long long sum(int l, int r, vector<long long> arr) {
            return arr[r] - (l > 0 ? arr[l - 1] : 0);
        }

        int max_score(int N, int X, int Y, long long K,
            vector<int> U, vector<int> V, vector<int> W) {
            pL.resize(N); pR.resize(N); pM.resize(N);
            for(int l = 0; l < N; l++) D[l][0] = D[l][1] = 2e18 + 7, adj[l].clear();
            for(int l = 0; l < N - 1; l++) {
                adj[U[l]].push_back({V[l], W[l]});
                adj[V[l]].push_back({U[l], W[l]});
            }
            if(X > Y) swap(X, Y);
            D[X][0] = 0, D[Y][1] = 0;
            dfs(X, X, 0); dfs(Y, Y, 1);
            for(int l = 0; l < N; l++) {
                pL[l] = D[l][0];
                pR[l] = D[l][1];
                pM[l] = min(D[l][0], D[l][1]);
                if(l > 0) {
                    pL[l] += pL[l - 1];
                    pR[l] += pR[l - 1];
                    pM[l] += pM[l - 1];
                }
            }
            
            priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> Q;
            Q.push({0, X}); Q.push({0, Y});
            vector<long long> dist(N, 1e18);
            dist[X] = dist[Y] = 0;
            int res = 0; long long cur = 0;
            while(!Q.empty()) {
                int A = Q.top().second;
                long long B = Q.top().first; Q.pop();
                if(cur + B > K) break;
                cur += B; res++;
                for(auto u : adj[A]) {
                    if(dist[u.first] > dist[A] + u.second) {
                        dist[u.first] = dist[A] + u.second;
                        Q.push({dist[u.first], u.first});
                    }
                }
            }
            
            for(int l = 0; l <= N; l++) {
                for(int i = l; i <= N; i++) {
                    long long calc = sum(l, i, pL) + sum(l, i, pR) - sum(l, i, pM);
                    if(calc > K) continue;
                    int cur = i - l + 1;
                    priority_queue<pair<int, long long>, vector<pair<int, long long>>, greater<pair<int, long long>>> pq;
                    if(i < N - 1) pq.push({D[i + 1][1], i + 1});
                    if(l > 0) pq.push({D[l - 1][0], l - 1});
                    while(!pq.empty()) {
                        int x = pq.top().second; long long w = pq.top().first;
                        pq.pop(); calc += w;
                        if(calc > K) break;
                        ++cur;
                        if(x > i && x < N - 1) pq.push({D[x + 1][1], x + 1});
                        if(x < l && x > 0) pq.push({D[x - 1][0], x - 1});
                    }
                    res = max(res, cur);
                }
            }
            return res;
        }

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 12
• Subtask 4: 0 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17