Submission #1267506

#	Time	Username	Problem	Language	Result	Execution time	Memory
1267506		firegirlwaterboy	Robot (JOI21_ho_t4)	C++20	100 / 100	905 ms	79144 KiB

Main

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef tuple<ll, int, int> tlii;

const ll INF = 1e18, MAXN = 1e5 + 1;

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

map<int, vector<Edge>> adj[MAXN];
ll dp[MAXN];
map<int, ll> dp2[MAXN], psum[MAXN];

void solve() {
    memset(dp, 0x3f, sizeof dp);
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int u, v, c;
        ll p;
        cin >> u >> v >> c >> p;
        adj[u][c].push_back({v, c, p}), adj[v][c].push_back({u, c, p});
        psum[u][c] += p, psum[v][c] += p;
    }
    dp[1] = 0;
    priority_queue<tlii> pq;
    pq.push({0, 1, 0});
    while (pq.size()) {
        ll cost;
        int node, c;
        tie(cost, node, c) = pq.top();
        pq.pop();
        if (c) {
            if (dp2[node][c] != -cost) continue;
            for (Edge i : adj[node][c]) {
                ll case1 = psum[node][c] - i.p;
                if (case1 - cost < dp[i.to]) {
                    dp[i.to] = case1 - cost;
                    pq.push({-dp[i.to], i.to, 0});
                }
            }
        } else {
            if (dp[node] != -cost) continue;
            for (auto &i : adj[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] > INF ? -1 : dp[n]) << "\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    solve();
    return 0;
}

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