Submission #1128129

#	Time	Username	Problem	Language	Result	Execution time	Memory
1128129		ngokhanh	Election Campaign (JOI15_election_campaign)	C++20	0 / 100	1096 ms	20220 KiB

election_campaign

#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for (int i=a;i<=b;i++)
#define rep2(i,a,b,c) for (int i=a;i<=b;i+=c)
#define rev(i,a,b) for (int i=a;i>=b;i--)
#define rev2(i,a,b,c) for (int i=a;i>=b;i-=c)
#define bit(i,j) ((i>>j)&1)
#define pii pair<int,int>
#define ull unsigned long long
#define pb push_back
#define pf push_front
#define ll long long
#define Fi first
#define Se second
#define sz(a) (ll)(a.size())
#define on(n) __builtin_popcountll(n)
#define ld long double
#define __log2(x) 31-__builtin_clz(x)
#define Mask(x) (1LL<<x)
#define ALL(v) v.begin(),v.end()

const int MAXN=1e5+5;
const int mod=998244353;

struct node{
    int u,v,w;
};

int n,u,v,m,a,b,c;
int up[MAXN][25],h[MAXN],dp[MAXN];
vector<int> g[MAXN];
vector<node> Path[MAXN];

void dfs(int u){
    for (int v:g[u]){
        if (v==up[u][0]) continue;
        up[v][0]=u;
        h[v]=h[u]+1;
        rep(i,1,20) up[v][i]=up[up[v][i-1]][i-1];
        dfs(v);
    }
}

int calc(int cur,int u){
    int sum=0;
    int prev=0;
    while(cur!=u){
        for (int v:g[cur]){
            if (v==prev||v==up[cur][0]) continue;
            sum+=dp[v];
        }
        prev=cur;
        cur=up[cur][0];
    }
    return sum;
}

int lca(int u,int v){
    if (h[u]<h[v]) swap(u,v);
    int k=h[u]-h[v];
    rep(i,0,__log2(k))
        if (bit(k,i)) u=up[u][i];
    if (u==v) return u;
    k=__log2(h[u]);
    rev(i,k,0)
        if (up[u][i]!=up[v][i])
            u=up[u][i],v=up[v][i];
    return up[u][0];
}

int jump(int u,int k){
    int cur=u;
    rep(i,0,__log2(k))
        if (bit(k,i)) cur=up[cur][i];
    return cur;
}

void calcdp(int u){
    for (int v:g[u]){
        if (v==up[u][0]) continue;
        calcdp(v);
    }
    int sum=0;
    for (int v:g[u]) sum+=dp[v];
    dp[u]=max(dp[u],sum);
    if (!Path[u].empty()){
        for (node tmp:Path[u]){
            int sum=calc(tmp.u,u)+calc(tmp.v,u);
            int A=jump(tmp.u,h[tmp.u]-h[u]-1);
            int B=jump(tmp.v,h[tmp.v]-h[u]-1);
            for (int v:g[u]){
                if (v==A||v==B||v==up[u][0]) continue;
                sum+=dp[v];
            }
            dp[u]=max(dp[u],sum+tmp.w);
        }
    }
}

void solution(){
    cin >> n;
    rep(i,1,n-1){
        cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
    dfs(1);
    cin >> m;
    rep(i,1,m){
        cin >> a >> b >> c;
        int x=lca(a,b);
        Path[x].pb({a,b,c});
    }
    calcdp(1);
    cout << dp[1];
}

int32_t main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int test=1;
    while(test--)
        solution();
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 5
• Subtask 3: 0 / 5
• Subtask 4: 0 / 30
• Subtask 5: 0 / 10
• Subtask 6: 0 / 40