Submission #1147069

#	Time	Username	Problem	Language	Result	Execution time	Memory
1147069		Luvidi	Roadside Advertisements (NOI17_roadsideadverts)	C++20	7 / 100	1096 ms	9284 KiB

roadsideadverts

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

#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fs first
#define sc second
#define pb push_back

const int maxn=5e4;
vector<pii> adj[maxn];
int dp[maxn],up[maxn][20];
ll d[maxn];

void dfs(int v,int p){
    up[v][0]=p;
    for(auto[u,w]:adj[v])if(u!=p){
        d[u]=d[v]+w;
        dp[u]=dp[v]+1;
        dfs(u,v);
    }
}

int lca(int u,int v){
    if(dp[u]<dp[v])swap(u,v);
    for(int i=19;i>-1;i--)if(dp[u]-(1<<i)>=dp[v])u=up[u][i];
    if(u==v)return u;
    for(int i=19;i>-1;i--)if(up[u][i]!=up[v][i])u=up[u][i],v=up[v][i];
    return up[u][0];
}

int dist(int u,int v){
    return d[u]+d[v]-2*d[lca(u,v)];
}

void solve() {
    int n;
    cin>>n;
    for(int i=0;i<n-1;i++){
        int u,v,w;
        cin>>u>>v>>w;
        adj[u].pb({v,w});
        adj[v].pb({u,w});
    }
    dfs(0,0);
    for(int x=1;x<20;x++){
        for(int i=0;i<n;i++)up[i][x]=up[up[i-1][x-1]][x-1];
    }
    int q;
    cin>>q;
    while(q--){
        int a[5];
        for(int i=0;i<5;i++)cin>>a[i];
        int ans=0;
        int d[5][n];
        for(int i=0;i<5;i++){
            for(int j=0;j<n;j++)d[i][j]=dist(a[i],j);
        }
        for(int i=0;i<n;i++){
            for(auto[j,w]:adj[i])if(i<j){
                bool b=0;
                for(int x=0;x<5;x++){
                    for(int y=0;y<5;y++){
                        b|=d[x][i]+w+d[y][j]==d[x][a[y]];
                    }
                }
                if(b)ans+=w;
            }
        }
        cout<<ans<<'\n';
    }
}

int main() {
    #ifdef FPO
        freopen("in","r",stdin);
        freopen("out","w",stdout);
    #endif
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    solve();
}

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