Submission #1069698

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069698		thangdz2k7	Cyberland (APIO23_cyberland)	C++17	100 / 100	1559 ms	10588 KiB

cyberland

#include <bits/stdc++.h>
#define db double

using namespace std;

const db inf = 1e18;
const db mid = 2.0;

db solve(int N, int M, int K, int H, vector <int> x, vector <int> y, vector <int> c, vector <int> arr){
    K = min(K, 100);

    vector <vector <int>> adj(N);
    for (int i = 0; i < M; ++ i) adj[x[i]].push_back(i), adj[y[i]].push_back(i);
    vector <db> dp(N, inf);
    dp[0] = 0.0; db ans = inf;

    for (int loops = 0; loops <= K; ++ loops){
        priority_queue <pair <db, int>> qu;
        vector <db> rd(N, inf);
        for (int u = 0; u < N; ++ u){
            if (dp[u] == inf || (u > 0 && arr[u] == 1)) continue;
            if (arr[u] == 0) rd[u] = 0.0;
            qu.push({-dp[u] / mid, u});
        }

        while (qu.size()){
            auto [du, u] = qu.top();
            qu.pop(); du = -du;
            if (u == H) continue;
            for (int id : adj[u]){
                int v = x[id] ^ y[id] ^ u;
                if (rd[v] > du + c[id]){
                    if (arr[v] == 0) rd[v] = 0;
                    else rd[v] = du + c[id];
                    qu.push({-rd[v], v});
                }
            }
        }

        if (!loops && rd[H] == inf) break;
        dp = rd;
        ans = min(ans, dp[H]);
    }

    if (ans == inf) return -1;
    return ans;
}

//void solve(){
//    int N, M, K; cin >> N >> M >> K;
//    int H; cin >> H;
//    vector <int> arr(N); for (int i = 0; i < N; ++ i) cin >> arr[i];
//    vector <int> x(M), y(M), z(M); for (int i = 0; i < M; ++ i) cin >> x[i] >> y[i] >> z[i];
//    cout << fixed << setprecision(10) << solve(N, M, K, H, x, y, z, arr) << '\n';
//}
//
//int main(){
//    freopen("cyberland.inp", "r", stdin);
//    freopen("cyberland.out", "w", stdout);
////    ios_base::sync_with_stdio(0);
////    cin.tie(0);
////    cout.tie(0);
//
//    int t = 1;
//    while (t --) solve();
//
//    return 0;
//}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 19 / 19
• Subtask 5: 7 / 7
• Subtask 6: 16 / 16
• Subtask 7: 29 / 29
• Subtask 8: 3 / 3