結果

問題 No.2949 Product on Tree
ユーザー pitP
提出日時 2024-10-25 22:17:42
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 420 ms / 2,000 ms
コード長 5,061 bytes
コンパイル時間 7,016 ms
コンパイル使用メモリ 336,724 KB
実行使用メモリ 59,368 KB
最終ジャッジ日時 2024-10-25 22:18:08
合計ジャッジ時間 24,555 ms
ジャッジサーバーID
（参考情報） 		judge1 / judge3
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 3
other AC * 46
権限があれば一括ダウンロードができます

ソースコード

diff #
プレゼンテーションモードにする

#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
istream &operator>>(istream &is, modint &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint &a) { return os << a.val(); }
istream &operator>>(istream &is, modint998244353 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint998244353 &a) { return os << a.val(); }
istream &operator>>(istream &is, modint1000000007 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint1000000007 &a) { return os << a.val(); } 
typedef long long ll;
typedef vector<vector<int>> Graph;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define FOR(i,l,r) for (int i = l;i < (int)(r); i++)
#define rep(i,n) for (int i = 0;i < (int)(n); i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define my_sort(x) sort(x.begin(), x.end())
#define my_max(x) *max_element(all(x))
#define my_min(x) *min_element(all(x))
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
const int INF = (1<<30) - 1;
const ll LINF = (1LL<<62) - 1;
const int MOD = 998244353;
const int MOD2 = 1e9+7;
const double PI = acos(-1);
vector<int> di = {1,0,-1,0};
vector<int> dj = {0,1,0,-1};
#ifdef LOCAL
#  include <debug_print.hpp>
#  define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define debug(...) (static_cast<void>(0))
#endif
using mint = modint998244353;
template<class E, class V, E (*merge)(E, E), E (*e)(), E (*put_edge)(V, int), V (*put_vertex)(E, int)>
struct RerootingDP {
    struct edge{
        int from, to, idx, rev_idx;
    };
    RerootingDP (int _n = 0) : n(_n) { es.resize(n);}
    void add_edge(int u, int v, int idx1, int idx2){
        es[u].push_back({u,v,idx1,idx2});
        es[v].push_back({v,u,idx2,idx1});
    }
    V build(int v = 0){
        root = v;
        vis.resize(n,0);
        outs.resize(n);
        return dfs(root);
    }
    vector<V> reroot(){
        reverse_edge.resize(n);
        reverse_edge[root] = e();
        answers.resize(n);
        bfs(root);
        return answers;
    }
  private:
    int n, root;
    vector<vector<edge>> es;
    vector<int> vis;
    vector<vector<E>> outs;
    vector<E> reverse_edge;
    vector<V> answers;
    V dfs(int v){
        vis[v]++;
        E val = e();
        for (auto &p : es[v]){
            if (vis[p.to] > 0 && p.to != es[v].back().to) swap(p,es[v].back());
            if (vis[p.to] > 0) continue;
            E nval = put_edge(dfs(p.to),p.idx);
            outs[v].emplace_back(nval);
            val = merge(val,nval);
        }
        return put_vertex(val,v);
    }
    void bfs(int v){
        int siz = outs[v].size();
        vector<E> lui(siz+1), rui(siz+1);
        lui[0] = e(), rui[siz] = e();
        for (int i = 0; i < siz; i++) lui[i+1] = merge(lui[i],outs[v][i]);
        for (int i = siz-1; i >= 0; i--) rui[i] = merge(outs[v][i],rui[i+1]);
        for (int i = 0; i < siz; i++){
            reverse_edge[es[v][i].to] = put_edge(put_vertex(merge(merge(lui[i],rui[i+1]),reverse_edge[v]),v),es[v][i].rev_idx);
            bfs(es[v][i].to);
        }
        answers[v] = put_vertex(merge(lui[siz],reverse_edge[v]), v);
    }
};
// Education dp subtree
// https://atcoder.jp/contests/dp/submissions/37662999
using T_monoid = mint; // E
using T_DP = mint; // V
mint A[202020];
T_monoid merge(T_monoid a, T_monoid b){
    debug(a, b);
    return a + b;
}
T_monoid e(){
    return (mint)0;
}
T_monoid put_edge(T_DP x, int i){
    return x;
}
T_DP put_vertex(T_monoid x, int v){
    debug(x, v, A[v]);
    return (x + 1) * A[v];
}
// 参考
// https://trap.jp/post/1702/
// https://null-mn.hatenablog.com/entry/2020/04/14/124151 
// fがput_edge, gがput_vertex
// 辺の情報が必要なときはedge[i]を作る、また頂点の情報が必要な時はvertex[v]を作る
int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    int N; cin >> N;
    rep(i, N) cin >> A[i];
    // Graph g(N);
    // rep(i, N - 1){
    //     int U, V;
    //     cin >> U >> V;
    //     U--;
    //     V--;
    //     g[U].push_back(V);
    //     g[V].push_back(U);
    // }
    // function<mint(int, int)> dfs = [&](int now, int par){
    //     mint res = 1;
    //     for(int nxt : g[now])if(nxt != par){
    //         res += dfs(nxt, now);
    //     }
    //     res *= A[now];
    //     return res;
    // };
    RerootingDP<T_monoid, T_DP, merge, e, put_edge, put_vertex> g(N);
    rep(i, N - 1){
        int U, V;
        cin >> U >> V;
        U--;
        V--;
        g.add_edge(U, V, i, i);
    }
    g.build(0);
    vector<mint> B = g.reroot();
    debug(B);
    // vector<mint> B(N);
    mint ans = 0;
    // rep(i, N) {
    //     B[i] = dfs(i, -1);
    //     ans += B[i];
    // }
    rep(i, N) ans += B[i] - (mint)A[i];
    cout << ans / (mint)2 << endl;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0