Submission #1037767

#	Time	Username	Problem	Language	Result	Execution time	Memory
1037767		fv3	Closing Time (IOI23_closing)	C++17	0 / 100	242 ms	10756 KiB

closing

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

using namespace std;
typedef long long ll;

const ll INF = 1ll << 60ll;

int max_score(int N, int X, int Y, ll K,
              vector<int> U, vector<int> V, vector<int> W)
{
    // Subtask 4:
    // Find optimal distance X should move to the right
    // O(N²)

    int best = 0;
    for (int r = X; r < N; r++)
    {
        vector<ll> closingTime(N);

        int res = 0;
        ll k_sum = 0;

        for (int i = X + 1; i <= r; i++)
        {
            k_sum += closingTime[i-1] + W[i];
            closingTime[i] = closingTime[i-1] + W[i];
            res++;
        }
        if (k_sum > K)
            break;

        priority_queue<pair<ll, pair<int, int>>> q;
        q.push({0, {X, 0}});
        q.push({0, {Y, 1}});

        vector<ll> dist(N), distY(N, INF);
        distY[Y] = 0;

        vector<int> visited(N);

        while (!q.empty())
        {
            int t = q.top().second.second;
            int s = q.top().second.first;
            q.pop();

            if (t == 0)
            {
                // X - can only go left
                if (k_sum + dist[s] > K)
                    break;
                k_sum += dist[s];
                res++;

                if (s)
                {
                    dist[s-1] = dist[s] + W[s-1];
                    q.push({-dist[s-1], {s-1, 0}});
                }
            }
            else
            {
                // Y - can go either way
                ll addedDist = max(0ll, distY[s] - dist[s]);

                if (k_sum + addedDist > K)
                    break;
                k_sum += addedDist;
                res++;

                visited[s] = 1;
                if (s && !visited[s-1])
                {
                    // Go left
                    distY[s-1] = distY[s] + W[s-1];
                    q.push({-max(0ll, distY[s-1] - dist[s-1]), {s-1, 1}});
                }
                if (s < N - 1 && !visited[s+1])
                {
                    // Go right
                    distY[s+1] = distY[s] + W[s];
                    q.push({-max(0ll, distY[s+1] - dist[s+1]), {s+1, 1}});
                }
            }
        }

        best = max(best, res);
    }

    return best;

    /*
    priority_queue<pair<ll, int>> q;
    q.push({0, X});
    q.push({0, Y});

    vector<int> visited(N);
    dist[Y] = 0;

    int res = 0;
    while (!q.empty())
    {
        int s = q.top().second;
        q.pop();

        if (visited[s]) 
            continue;
        visited[s] = 1;

        K -= dist[s];
        if (K < 0)
            break;
        res++;

        for (auto node : adj[s])
        {
            if (!visited[node.first] && dist[s] + node.second < dist[node.first])
            {
                dist[node.first] = dist[s] + node.second;
                q.push({-dist[node.first], node.first});
            }
        }
    }

    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