Submission #970703

#	Time	Username	Problem	Language	Result	Execution time	Memory
970703		htphong0909	Robot (JOI21_ho_t4)	C++17	34 / 100	3075 ms	118004 KiB

Main

#include <bits/stdc++.h>
#define int long long
using namespace std;

map<int, vector<pair<int, int>>> adj[100001];
unordered_map<int, int> D[100001];
unordered_map<int, int> sum[100001];
map<int, pair<int, int>> edge[100001];

int32_t main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    //freopen("TEST.in", "r", stdin);
    //freopen("TEST.out", "w", stdout);
    int n, m;
    cin >> n >> m;
    map<int, vector<pair<int, int>>> test;
    for (int i = 0; i < m; i++)
    {
        int u, v, c, w;
        cin >> u >> v >> c >> w;
        adj[u][c].emplace_back(v, w);
        adj[v][c].emplace_back(u, w);
        sum[u][c] += w;
        sum[v][c] += w;
        edge[u][v] = {c, w};
        edge[v][u] = {c, w};
    }
    D[1][0] = 1;
    priority_queue<array<int, 3>, vector<array<int, 3>>, greater<>> q;
    q.push({1, 1, 0});
    while (!q.empty())
    {
        int d = q.top()[0];
        int u = q.top()[1];
        int t = q.top()[2];
        //cerr << u << " " << t << " " << d - 1 << endl;
        int pc, pw;
        if (t == 0) tie(pc, pw) = make_pair(-1, 0);
        else tie(pc, pw) = edge[u][t];
        q.pop();
        for (const auto& [c, l] : adj[u])
        {
            int sz = (int)l.size();
            int s = sum[u][c];
            if (pc == c)
            {
                sz--;
                s -= pw;
            }
            for (const auto& [v, w] : l)
            {
                if (v == t) continue;
                if (D[u][t] + w < D[v][u] || !D[v][u])
                {
                    D[v][u] = D[u][t] + w;
                    q.push({D[v][u], v, u});
                }
                /*if (sz == 1 && (D[u][t] < D[v][u] || !D[v][u]))
                {
                    D[v][u] = D[u][t];
                    q.push({D[v][u], v, u});
                }*/
                if (D[u][t] + s - w < D[v][0] || !D[v][0])
                {
                    D[v][0] = D[u][t] + s - w;
                    q.push({D[v][0], v, 0});
                }
            }
        }
    }
    int ans = (int)1e18;
    for (const auto& [t, dis] : D[n]) ans = min(ans, dis);
    if (ans == (int)1e18) cout << -1;
    else cout << ans - 1;
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int32_t main()':
Main.cpp:35:13: warning: unused variable 'd' [-Wunused-variable]
   35 |         int d = q.top()[0];
      |             ^

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