Submission #981110

#	Time	Username	Problem	Language	Result	Execution time	Memory
981110		0x34c	Robot (JOI21_ho_t4)	C++17	34 / 100	3038 ms	69496 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;
};

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

class Compare {
public:
    bool operator()(tuple<int, int, int, int> &a, tuple<int, 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);
    for(int i = 0; i < M; i++) {
        int a, b, c, w;
        cin >> a >> b >> c >> w;

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

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

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

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

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

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