Submission #773290

#	Time	Username	Problem	Language	Result	Execution time	Memory
773290		AmirElarbi	Cyberland (APIO23_cyberland)	C++17	97 / 100	3041 ms	70792 KiB

cyberland

#include <bits/stdc++.h>
#define ve vector
#define vi vector<int>
#define vii vector<ii>
#define ii pair<int,int>
#define fi first
#define se second
#define ll long long
#define INF 1e18+7
#define pb push_back
#define optimise ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using Tree = tree<T, null_type, less<T>, rb_tree_tag,
    tree_order_statistics_node_update>;
const int MOD = 1e9+7;
const int nax = 2e5+5;
const int kax = 30+5;
void readio(){
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif
}
#include "cyberland.h"
vii adj[nax];
bool vis[nax];
double dist[nax][kax];
void dfs(int u, int nt){
    if(vis[u]) return;
    vis[u] = 1;
    for(auto x : adj[u]){
        if(x.fi == nt) continue;
        dfs(x.fi, nt);
    }
}
double solve(int n, int m, int k, int h, vi x, vi y, vi c, vi arr) {
    for (int i = 0; i < n; ++i)
    {
        adj[i].clear();
        vis[i] = 0;
        for (int j = 0; j <= k; ++j)
        {
            dist[i][j] = INF;   
        }
    }
    for (int i = 0; i < m; ++i)
    {
        adj[x[i]].pb({y[i], c[i]});
        adj[y[i]].pb({x[i], c[i]});
    }
    dfs(0,h);
    priority_queue<pair<pair<double,int>,int>, ve<pair<pair<double,int>,int>>, greater<pair<pair<double,int>,int>>> pq;
    for (int i = 0; i < n; ++i)
    {
        if((arr[i] == 0 && vis[i])|| !i){
            dist[i][0] = 0;
            pq.push({{0,0}, i});
        }
    }
    while(!pq.empty()){
        int u = pq.top().se, nb = pq.top().fi.se;
        double cst = pq.top().fi.fi;
        pq.pop();
        if(dist[u][nb] != cst) continue;
        if(u == h) continue;
        for(auto x : adj[u]){
            if(dist[u][nb]+x.se < dist[x.fi][nb]){
                dist[x.fi][nb] = dist[u][nb]+x.se;
                pq.push({{dist[x.fi][nb], nb}, x.fi});
            }
            if(nb < k && arr[x.fi] == 2 && (dist[u][nb]+x.se)*0.5 < dist[x.fi][nb+1]){
                dist[x.fi][nb+1] = (dist[u][nb]+x.se)*0.5;
                pq.push({{dist[x.fi][nb+1], nb+1}, x.fi});
            }
        }
    }
    double ans = INF;
    for (int i = 0; i <= k; ++i)
    {
        ans = min(ans, dist[h][i]);
    }
    if(ans == INF) return -1;
    return ans;
}

Compilation message (stderr)

cyberland.cpp: In function 'void readio()':
cyberland.cpp:23:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
cyberland.cpp:24:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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