Submission #415842

#	Time	Username	Problem	Language	Result	Execution time	Memory
415842		ruadhan	Robot (JOI21_ho_t4)	C++17	100 / 100	1405 ms	84392 KiB

Main

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

const ll INF = 1e18;

struct Edge
{
    int to, c;
    ll p;
};

map<int, vector<Edge>> graph[100001];
ll dp[100001];
map<int, ll> dp2[100001], psum[100001];

int main()
{
    int N, M;
    cin >> N >> M;
    for (int i = 0; i < M; i++)
    {
        int u, v, c;
        ll p;
        cin >> u >> v >> c >> p;
        graph[u][c].push_back({v, c, p});
        graph[v][c].push_back({u, c, p});
        psum[u][c] += p;
        psum[v][c] += p;
    }

    for (int i = 0; i <= N; i++)
        dp[i] = LONG_LONG_MAX;

    dp[1] = 0;
    using T = tuple<ll, int, int>;
    priority_queue<T, vector<T>, greater<T>> pq;
    pq.push({0, 1, 0});

    while (!pq.empty())
    {
        ll cost;
        int node, c;
        tie(cost, node, c) = pq.top();
        pq.pop();
        if (c)
        {
            if (dp2[node][c] != cost)
                continue;
            for (Edge i : graph[node][c])
            {
                ll case1 = psum[node][c] - i.p + cost;
                if (case1 < dp[i.to])
                {
                    dp[i.to] = case1;
                    pq.push({dp[i.to], i.to, 0});
                }
            }
        }
        else
        {
            if (dp[node] != cost)
                continue;
            for (auto &i : graph[node])
            {
                for (Edge j : i.second)
                {
                    ll case1 = psum[node][j.c] - j.p + cost;
                    if (case1 < dp[j.to])
                    {
                        dp[j.to] = case1;
                        pq.push({dp[j.to], j.to, 0});
                    }

                    ll case2 = j.p + cost;
                    if (case2 < dp[j.to])
                    {
                        dp[j.to] = case2;
                        pq.push({dp[j.to], j.to, 0});
                    }

                    ll case3 = cost;
                    if (!dp2[j.to].count(j.c) || case3 < dp2[j.to][j.c])
                    {
                        dp2[j.to][j.c] = case3;
                        pq.push({dp2[j.to][j.c], j.to, j.c});
                    }
                }
            }
        }
    }

    cout << (dp[N] == LONG_LONG_MAX ? -1 : dp[N]) << '\n';

    return 0;
}

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