結果

問題 No.2949 Product on Tree
ユーザー GOTKAKOGOTKAKO
提出日時 2024-10-25 22:08:34
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 1,335 ms / 2,000 ms
コード長 3,953 bytes
コンパイル時間 2,661 ms
コンパイル使用メモリ 218,324 KB
実行使用メモリ 30,308 KB
最終ジャッジ日時 2024-10-25 22:09:40
合計ジャッジ時間 49,982 ms
ジャッジサーバーID
(参考情報)
judge3 / judge5
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 2 ms
6,816 KB
testcase_01 AC 2 ms
6,816 KB
testcase_02 AC 1 ms
6,820 KB
testcase_03 AC 780 ms
15,820 KB
testcase_04 AC 821 ms
15,324 KB
testcase_05 AC 917 ms
15,816 KB
testcase_06 AC 849 ms
15,800 KB
testcase_07 AC 868 ms
15,452 KB
testcase_08 AC 833 ms
16,080 KB
testcase_09 AC 1,010 ms
16,196 KB
testcase_10 AC 978 ms
16,832 KB
testcase_11 AC 1,057 ms
17,908 KB
testcase_12 AC 1,047 ms
19,864 KB
testcase_13 AC 1,147 ms
20,568 KB
testcase_14 AC 1,107 ms
21,984 KB
testcase_15 AC 1,141 ms
24,204 KB
testcase_16 AC 1,096 ms
22,444 KB
testcase_17 AC 1,248 ms
23,196 KB
testcase_18 AC 1,218 ms
23,000 KB
testcase_19 AC 1,254 ms
25,124 KB
testcase_20 AC 1,300 ms
24,612 KB
testcase_21 AC 1,309 ms
24,860 KB
testcase_22 AC 1,240 ms
26,016 KB
testcase_23 AC 821 ms
16,028 KB
testcase_24 AC 884 ms
16,020 KB
testcase_25 AC 911 ms
15,920 KB
testcase_26 AC 927 ms
16,012 KB
testcase_27 AC 964 ms
16,196 KB
testcase_28 AC 943 ms
16,232 KB
testcase_29 AC 1,001 ms
16,640 KB
testcase_30 AC 1,076 ms
17,048 KB
testcase_31 AC 1,108 ms
18,040 KB
testcase_32 AC 1,146 ms
19,404 KB
testcase_33 AC 1,211 ms
21,936 KB
testcase_34 AC 1,284 ms
26,288 KB
testcase_35 AC 1,229 ms
23,648 KB
testcase_36 AC 1,280 ms
28,024 KB
testcase_37 AC 1,330 ms
28,404 KB
testcase_38 AC 1,295 ms
25,328 KB
testcase_39 AC 1,335 ms
25,876 KB
testcase_40 AC 1,317 ms
29,872 KB
testcase_41 AC 1,276 ms
27,344 KB
testcase_42 AC 1,274 ms
30,308 KB
testcase_43 AC 93 ms
15,008 KB
testcase_44 AC 93 ms
15,220 KB
testcase_45 AC 120 ms
18,368 KB
testcase_46 AC 107 ms
16,832 KB
testcase_47 AC 80 ms
13,188 KB
testcase_48 AC 111 ms
17,264 KB
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 #

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

long long mod = 998244353;
//入力が必ず-mod<a<modの時.
struct mint{
    long long v = 0;
    mint(){} mint(int a){v = a<0?a+mod:a;} mint(long long a){v = a<0?a+mod:a;}
    mint(unsigned long long a){v = a;}
    long long val(){return v;}
    void modu(){v %= mod;}
 
    mint repeat2mint(const long long a,long long b){
        mint ret = 1,p = a;
        while(b){
            if(b&1) ret *= p;
            p *= p; b >>= 1;
        }
        return ret;
    };
 
    mint &operator=(const mint &b) = default;
    mint operator-() const {return mint(0)-(*this);}
    mint operator+(const mint b){return mint(v)+=b;}
    mint operator-(const mint b){return mint(v)-=b;}
    mint operator*(const mint b){return mint(v)*=b;}
    mint operator/(const mint b){return mint(v)/=b;}
 
    mint operator+=(const mint b){
        v += b.v; if(v >= mod) v -= mod;
        return *this;
    }
    mint operator-=(const mint b){
        v -= b.v; if(v < 0) v += mod; 
        return *this;
    }   
    mint operator*=(const mint b){v = v*b.v%mod; return *this;}
    mint operator/=(mint b){
        if(b == 0) assert(false);
        int left = mod-2;
        while(left){if(left&1) *this *= b; b *= b; left >>= 1;}
        return *this;
    }
 
    mint operator++(int){*this += 1; return *this;}
    mint operator--(int){*this -= 1; return *this;}
    bool operator==(const mint b){return v == b.v;}
    bool operator!=(const mint b){return v != b.v;}
    bool operator>(const mint b){return v > b.v;}
    bool operator>=(const mint b){return v >= b.v;}
    bool operator<(const mint b){return v < b.v;}
    bool operator<=(const mint b){return v <= b.v;}
 
    mint pow(const long long x){return repeat2mint(v,x);}
    mint inv(){return mint(1)/v;}
};

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int N; cin >> N;
    vector<mint> A(N);
    for(auto &a : A) cin >> a.v;

    vector<vector<int>> Graph(N);
    for(int i=0; i<N-1; i++){
        int u,v; cin >> u >> v;
        u--; v--;
        Graph.at(u).push_back(v);
        Graph.at(v).push_back(u);
    }

    vector<bool> stop(N);
    auto findsiz = [&](auto&& self,int pos,int back) -> int {
        if(stop.at(pos)) return 0;
        int ret = 1;
        for(auto to : Graph.at(pos)) if(to != back) ret += self(self,to,pos);
        return ret;
    };
    auto findcent = [&](int start) -> int {
        int siz = findsiz(findsiz,start,-1);
        int cent = -1;
        auto dfs = [&](auto dfs,int pos,int back) -> int {
            if(stop.at(pos)) return 0;
            int ret = 0;
            bool iscent = true;
            for(auto to : Graph.at(pos)) if(to != back){
                int ko = dfs(dfs,to,pos);
                if(ko > siz/2) iscent = false;
                ret += ko;
            } 
            ret++;
            if(siz-ret > siz/2) iscent = false;
            if(iscent) cent = pos;
            return ret;
        };
        dfs(dfs,start,-1);
        return cent;
    };

    mint answer = 0;
    queue<int> Q; Q.push(0);
    mint div2 = mint(1)/2;
    while(Q.size()){
        int start = Q.front(); Q.pop();
        int cent = findcent(start); 

        int n = Graph.at(cent).size();
        vector<mint> sum(n);
        auto dfs = [&](auto dfs,int pos,int back,mint now,int i) -> void {
            if(stop.at(pos)) return;
            now *= A.at(pos);
            sum.at(i) += now;
            for(auto to : Graph.at(pos)) if(to != back) dfs(dfs,to,pos,now,i);
        };
        for(int i=0; i<n; i++) dfs(dfs,Graph.at(cent).at(i),cent,1,i);

        mint all = 0;
        for(auto v : sum) all += v,answer += A.at(cent)*v;
        for(auto v : sum) answer += A.at(cent)*(all*v-v*v)*div2;

        stop.at(cent) = true;
        for(int i=0; i<n; i++){
            int to = Graph.at(cent).at(i);
            if(!stop.at(to)) Q.push(to);
        }
    }
    cout << answer.v << endl;
}
0