結果
| 問題 |
No.2115 Making Forest Easy
|
| コンテスト | |
| ユーザー |
沙耶花
|
| 提出日時 | 2022-10-28 22:41:20 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 782 ms / 2,000 ms |
| コード長 | 2,719 bytes |
| コンパイル時間 | 4,914 ms |
| コンパイル使用メモリ | 262,484 KB |
| 最終ジャッジ日時 | 2025-02-08 14:49:50 |
|
ジャッジサーバーID (参考情報) |
judge2 / judge1 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 50 |
ソースコード
#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001
template <class Ss, Ss (*op0)(Ss, Ss), Ss (*e)(), class Sv, Ss (*op1)(Sv, Ss), class Se, Ss (*op2)(Se, Ss)>
struct rerooting{
int n;
vector<vector<int>> to;
vector<vector<Se>> edge;
vector<Ss> subtree,answer;
vector<Sv> vertex;
rerooting(int _n){
n = _n;
to.resize(n);
edge.resize(n);
subtree.resize(n,e());
answer.resize(n,e());
vertex.resize(n);
}
rerooting(vector<Sv> v){
n = v.size();
to.resize(n);
edge.resize(n);
subtree.resize(n,e());
answer.resize(n,e());
vertex = v;
}
void add_directed_edge(int u,int v,Se x){
to[u].push_back(v);
edge[u].push_back(x);
}
void add_edge(int u,int v,Se x){
add_directed_edge(u,v,x);
add_directed_edge(v,u,x);
}
void solve(){
dfs(0,-1);
redfs(0,-1,e());
}
void dfs(int cur,int par){
Ss temp = e();
for(int i=0;i<to[cur].size();i++){
int nxt = to[cur][i];
if(nxt==par)continue;
dfs(nxt,cur);
temp = op0(temp, op2(edge[cur][i], subtree[nxt]));
}
subtree[cur] = op1(vertex[cur], temp);
}
void redfs(int cur, int par, Ss ps){
vector<Ss> P(to[cur].size()+1,e());
rep(i,to[cur].size()){
int nxt = to[cur][i];
if(nxt!=par)P[i+1] = op2(edge[cur][i], subtree[nxt]);
else P[i+1] = op2(edge[cur][i], ps);
}
vector<Ss> S(P.rbegin(),P.rend()-1);
S.insert(S.begin(),e());
rep(i,to[cur].size()){
P[i+1] = op0(P[i], P[i+1]);
S[i+1] = op0(S[i+1], S[i]);
}
answer[cur] = op1(vertex[cur], P.back());
for(int i=0;i<to[cur].size();i++){
int nxt = to[cur][i];
if(nxt!=par){
redfs(nxt,cur,op1(vertex[cur], op0(P[i],S[to[cur].size()-1-i])));
}
}
}
};
using A = array<mint,1005>;
A e(){
A ret;
rep(i,1005)ret[i] = 0;
ret[0] = 1;
return ret;
}
A op0(A a,A b){
rep(i,1004){
a[i+1] += a[i];
b[i+1] += b[i];
}
A ret = e();
ret[0] = 0;
rep(i,1005){
if(i==0)ret[i] = a[i]*b[i];
else{
ret[i] += (a[i]-a[i-1]) * (b[i]-b[i-1]);
ret[i] += (a[i]-a[i-1]) * b[i-1];
ret[i] += a[i-1] * (b[i]-b[i-1]);
}
}
return ret;
}
A op1(int a,A b){
rep(i,a){
b[a] += b[i];
b[i] = 0;
}
return b;
}
A op2(int a,A b){
mint s = 0;
rep(i,1003)s += b[i];
b[0] += s;
return b;
}
int main(){
int n;
cin>>n;
vector<int> a(n);
rep(i,n)cin>>a[i];
rerooting<A,op0,e,int,op1,int,op2> R(a);
rep(i,n-1){
int u,v;
cin>>u>>v;
R.add_edge(u-1,v-1,1);
}
R.solve();
mint ans = 0;
rep(i,n){
rep(j,1003){
ans += R.answer[i][j] * j;
}
}
cout<<ans.val()<<endl;
return 0;
}
沙耶花