Submission #981615

#	Time	Username	Problem	Language	Result	Execution time	Memory
981615		0x34c	Robot (JOI21_ho_t4)	C++17	34 / 100	3028 ms	82868 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define endl '\n'
#define int ll

using namespace std;

const int INF = 2e15;

struct nei
{
    int v, c, w, e_idx;
};

int N, M;
vector<vector<nei>> graph;
vector<map<int, int>> color_cost;
vector<pii> conv;

class Compare
{
public:
    bool operator()(tuple<int, int, int> &a, tuple<int, int, int> &b)
    {
        return get<0>(a) > get<0>(b);
    }
};

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin >> N >> M;

    graph.resize(N);
    color_cost.resize(N);
    conv.resize(M + 1, {0, 0});
    for (int i = 1; i <= M; i++)
    {
        int a, b, c, w;
        cin >> a >> b >> c >> w;

        --a;
        --b;
        --c;

        graph[a].push_back({b, c, w, i});
        graph[b].push_back({a, c, w, i});
        conv[i] = {c, w};
    }

    for (int i = 0; i < N; i++)
    {
        for (nei &u : graph[i])
            color_cost[i][u.c] += u.w;
    }

    vector<map<int, int>> dist(N);
    // wei, node, prev color, prev color weight
    priority_queue<tuple<int, int, int>, vector<tuple<int, int, int>>, Compare> q;
    dist[0][0] = 0;
    q.push({0, 0, 0});
    while (!q.empty())
    {
        int w, v, e_id;
        tie(w, v, e_id) = q.top();
        q.pop();

        if (dist[v][e_id] != w)
            continue;

        for (nei &u : graph[v])
        {
            int opt1 = w + u.w;
            if (!dist[u.v].count(u.e_idx) || dist[u.v][u.e_idx] > opt1)
            {
                dist[u.v][u.e_idx] = opt1;
                q.push({opt1, u.v, u.e_idx});
            }

            int pc, pw;
            tie(pc, pw) = conv[e_id];
            int opt2 = w + color_cost[v][u.c] - u.w - (pc == u.c ? pw : 0);
            if (!dist[u.v].count(0) || dist[u.v][0] > opt2)
            {
                dist[u.v][0] = opt2;
                q.push({opt2, u.v, 0});
            }
        }
    }

    int mn = INF;
    for (auto mp : dist[N - 1])
    {
        mn = min(mn, mp.second);
    }

    cout << (mn == INF ? -1 : mn) << endl;
}

• Subtask 1: 34 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42