Submission #1140911

#	Time	Username	Problem	Language	Result	Execution time	Memory
1140911		buzdi	Robot (JOI21_ho_t4)	C++17	0 / 100	347 ms	41436 KiB

Main

#include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
#define ll long long
#define ld long double

using namespace std;
using namespace __gnu_pbds;

typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

const int NMAX = 1e5;
const ll INF = 1e18;

struct PQElement {
    int node, parent, parent_c;
    ll d;
    bool operator < (const PQElement &other) const {
        return other.d < d;
    }
};

struct Edge {
    int next_node, c, p;
    Edge(int next_node, int c, int p) : next_node(next_node), c(c), p(p) {}
};

int n, m;
ll d[NMAX + 1];
vector<Edge> g[NMAX + 1];
unordered_map<int, int> mp[NMAX + 1];

void Dijkstra(int start) {
    for(int i = 1; i <= n; i++) {
        d[i] = INF;
    }

    priority_queue<PQElement> pq;
    pq.push({start, 0});
    while(!pq.empty()) {
        auto [node, parent, parent_c, curent_d] = pq.top();
        pq.pop();

        if(d[node] == INF) {
            d[node] = curent_d;
            for(auto [next_node, c, p] : g[node]) {
                if(mp[node][c] - (parent_c == c) == 1) {
                    pq.push({next_node, node, 0, curent_d});
                }
                else {
                    pq.push({next_node, node, c, curent_d + p});
                }
            }
        }
    }
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n >> m;
    for(int i = 1; i <= m; i++) {
        int a, b, c, p;
        cin >> a >> b >> c >> p;
        g[a].emplace_back(b, c, p);
        mp[a][c]++;
        g[b].emplace_back(a, c, p);
        mp[b][c]++; 
    }

    Dijkstra(1);
    cout << (d[n] == INF ? -1 : d[n]);

    return 0;
}

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