Submission #321726

#	Time	Username	Problem	Language	Result	Execution time	Memory
321726		wind_reaper	Roadside Advertisements (NOI17_roadsideadverts)	C++17	47 / 100	1038 ms	7864 KiB

roadsideadverts

// #define _GLIBCXX_DEBUG
// #pragma GCC optimize "trapv"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <chrono>

// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
// pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")

using namespace std;
using namespace __gnu_pbds;
using namespace chrono;

#define pb push_back 
#define f first
#define s second
#define min3(a, b, c) min(min(a, b), c)
#define max3(a, b, c) max(max(a, b), c)
#define all(v) v.begin(), v.end()

typedef long long ll;
typedef double ld;
typedef long double lld;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;

template <class T> using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;

const int INF = 1e9;
// const ll INF = 1e18;
const ll mod = 1000000007;
// const ll mod = 998244353;
vvi adj;
vpi dp;
vi tin, tout;
int timer;
vi sites;
void dfs(int node, int par){
    tin[node] = timer++;
    for(int e : adj[node]){
        if(e == par) continue;
        dfs(e, node);
        dp[node].f += dp[e].f;
    }

    if(sites[node]) 
        dp[node].f++;

    tout[node] = timer++;
}
bool is_anc(int u, int v){
    return tin[u] <= tin[v] && tout[u] >= tout[v];
}
void solve(int tc){
    int n;
    cin >> n;
    adj.resize(n);
    vector<array<int, 3>> edges;
    for(int i = 0; i < n-1; i++){
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].pb(v);
        adj[v].pb(u);
        edges.pb({u, v, w});
    }
    int q;
    cin >> q;
    for(int j = 0; j < q; j++){
        tin.resize(n), tout.resize(n);
        sites.assign(n, 0);
        for(int i = 0; i < 5; i++){
            int x;
            cin >> x;
            sites[x] = 1;
        }
        dp.assign(n, {0, 0});
        
        dfs(0, 0);
        
        for(int i = 0; i < n; i++)
            dp[i].s = 5 - dp[i].f;
        
        int ans = 0; 

        for(auto e : edges){
            if(is_anc(e[0], e[1])) 
                swap(e[0], e[1]);

            if(dp[e[0]].f > 0 && dp[e[0]].s > 0) 
                ans += e[2];
        }

        cout << ans << '\n';
    }   
}

int main(){
    ios_base::sync_with_stdio(NULL);
    cin.tie(NULL);
    #ifdef LOCAL
        auto begin = high_resolution_clock::now();
    #endif

    int tc = 1;
    // cin >> tc; 
    for (int t = 0; t < tc; t++) solve(t);
    
    #ifdef LOCAL 
        auto end = high_resolution_clock::now();
        cout << fixed << setprecision(4) << "Execution Time: " << duration_cast<duration<double>>(end - begin).count() << "seconds" << endl;
    #endif
    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 23
• Subtask 3: 40 / 40
• Subtask 4: 0 / 30