Submission #1161097

#	Time	Username	Problem	Language	Result	Execution time	Memory
1161097		daoquanglinh2007	Cyberland (APIO23_cyberland)	C++20	97 / 100	2387 ms	119996 KiB

cyberland

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

#define pii pair <int, int>
#define fi first
#define se second
#define mp make_pair

const int NM = 1e5, KM = 60;

const double inf = 1e18;

int N, M, K, H;
vector <pii> adj[NM+5];
vector <int> arr;
bool mark[NM+5];
double d[NM+5][KM+5][2];
priority_queue <pair <double, pii>, vector <pair <double, pii> >, greater <pair <double, pii> > > pq;
double ans;

void dfs(int u){
    mark[u] = 1;
    for (pii _ : adj[u]){
        int v = _.fi;
        if (v == H || mark[v]) continue;
        dfs(v);
    }
}

void dijkstra(){
    for (int t = 0; t <= K; t++){
        while (!pq.empty()) pq.pop();
        for (int i = 0; i < N; i++){
            if (t == 0){
                if (i == 0 || (arr[i] == 0 && mark[i])) d[i][t][0] = 0, d[i][t][1] = +inf;
                else d[i][t][0] = d[i][t][1] = +inf;
            }
            else{
                if (arr[i] == 2){
                    d[i][t][0] = d[i][t-1][0];
                    d[i][t][1] = d[i][t-1][1];
                    if (d[i][t-1][0] != +inf){
                        d[i][t][1] = min(d[i][t][1], d[i][t-1][0]*0.5);
                    }
                }
                else{
                    d[i][t][0] = d[i][t-1][0];
                    d[i][t][1] = +inf;
                }
                if (i == H) d[i][t][0] = d[i][t][1] = +inf;
            }
        }
        while (!pq.empty()) pq.pop();
        for (int i = 0; i < N; i++)
            for (int j = 0; j < 2; j++)
                pq.push(mp(d[i][t][j], mp(i, j)));
            
        while (!pq.empty()){
            int u = pq.top().se.fi, j = pq.top().se.se;
            if (d[u][t][j] != pq.top().fi){
                pq.pop();
                continue;
            }
            pq.pop();
            if (u == H || d[u][t][j] == +inf) continue;
            for (pii _ : adj[u]){
                int v = _.fi, c = _.se;
                if (d[u][t][j]+(double)c < d[v][t][0]){
                    d[v][t][0] = d[u][t][j]+(double)c;
                    pq.push(mp(d[v][t][0], mp(v, 0)));
                }
            }
        }
        ans = min(ans, d[H][t][0]);
    }
}

double solve(int _N, int _M, int _K, int _H, vector <int> x, vector <int> y, vector <int> c, vector <int> _arr){
    N = _N, M = _M, K = _K, H = _H;
    K = min(K, KM);
    for (int i = 0; i < N; i++){
        adj[i].clear();
        mark[i] = 0;
    }
    for (int i = 0; i < M; i++){
        adj[x[i]].push_back(mp(y[i], c[i]));
        adj[y[i]].push_back(mp(x[i], c[i]));
    }
    dfs(0);
    arr = _arr;
    
    ans = +inf;
    dijkstra();
    if (ans == +inf) ans = -1;
    return ans;
}

• 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: 0 / 3