Submission #917956

#	Time	Username	Problem	Language	Result	Execution time	Memory
917956		406	Robot (JOI21_ho_t4)	C++17	100 / 100	330 ms	142524 KiB

Main

#include <bits/stdc++.h>
#define int int64_t
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)

using namespace std;
using ar = array<int, 2>;
using ar3 = array<int, 3>;

const int64_t INF = 1ll << 60;
const int N = 2e6 + 5;

vector<ar3> adj[N];
int n, m, C[N], d[N], sum[N], P[N];
bool cnt[N];

signed main() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr); 
        cin >> n >> m;
        FOR(i, 0, m) {
                int u, v, c, p;
                cin >> u >> v >> c >> p;
                --u, --v;
                adj[v].push_back({u, c, p});
                adj[u].push_back({v, c, p});
        }
        int ptr = n - 1;
        vector<array<int, 4>> E;
        FOR(i, 0, n) {
                for (auto [u, c, p]: adj[i]) {
                        P[c] = (cnt[c] ? P[c] : ++ptr);
                        cnt[c] = true;
                        sum[c] += p;
                }
                /*
                for (auto &[u, c, p]: adj[i]) for (auto &[v, cv, pv]: adj[i]) if (cv == c && (u != v)) {
                        E.push_back({u, v, c, sum[c] - pv});
                }
                */
                for (auto [u, c, p]: adj[i]) {
                      E.push_back({u, P[c], c, 0});            
                      E.push_back({P[c], u, c, sum[c] - p});            
                }
                for (auto &[u, c, p]: adj[i]) {
                        p = min(p, sum[c] - p);
                        cnt[c] = 0;
                }
                for (auto [u, c, p]: adj[i]) sum[c] = 0;
        }
        for (auto [u, v, c, p]: E)
                adj[u].push_back({v, c, p});

        fill(d + 1, d + N, INF);
        priority_queue<ar> q;
        q.push({0, 0});
        while (q.size()) {
                auto [dist, v] = q.top();
                q.pop();
                if (-dist > d[v]) continue;

                for (auto [u, c, p]: adj[v]) {
                        int w = d[v] + p;
                        if (w < d[u]) {
                                q.push({-w, u});
                                d[u] = w;
                        }
                }
        }
        cout << (d[n - 1] < INF ? d[n - 1] : -1) << '\n';
        return 0;
}

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