#1157572 (C++23) No.3412 Christmas Tree Coloring

• 問題: No.3412 Christmas Tree Coloring
• ユーザー: くらげ
• 提出日時: 2026-04-17 17:49:20
• 言語: C++23 (gcc 15.2.0 + boost 1.89.0)
• 結果: AC
• 実行時間: 188 ms / 2,000 ms
• コード長: 3,119 bytes
• コンパイル時間: 3,320 ms
• コンパイル使用メモリ: 338,120 KB
• 実行使用メモリ: 6,400 KB
• 最終ジャッジ日時: 2026-04-17 17:49:33
• 合計ジャッジ時間: 12,419 ms
• ジャッジサーバーID （参考情報）: judge3_1 / judge1_1

ファイルパターン	結果
sample	AC * 2
other	AC * 20

ソースコード

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using vll = vector<ll>;
using pll = pair<ll,ll>;
#define rep(i,n) for(int i=0;i<(n);i++)
#define rrep(i,n) for(int i=(n)-1;0<=i;i--)
#define REP(i,n) for(int i=1;i<=n;i++)
#define all(a) a.begin(), a.end()
#define sort(a) sort(all(a))
#define rev(a) reverse(all(a))
char el = '\n';
void YN(bool f){cout<<(f?"Yes":"No")<<"\n";}
template<typename T> bool chmin(T& x,T y){if(x>y){x=y;return true;}return false;}
template<typename T> bool chmax(T& x,T y){if(x<y){x=y;return true;}return false;}
template<typename T> istream &operator>>(istream &is,pair<T,T> &v){is>>v.first>>v.second;return is;}
template<typename T> istream &operator>>(istream &is,vector<T> &v){for(T &in:v)is>>in;return is;}
template<typename T> ostream &operator<<(ostream &os,pair<T,T> &v){os<<v.first<<" "<<v.second;return os;}
template<typename T> ostream &operator<<(ostream &os,vector<T> &v){rep(i,v.size())os<<v[i]<<(i+1==v.size()?"":" ");return os;}

template<ll mod> struct modint{
    public:
    ll x;
    modint(ll x=0) : x((x%mod+mod)%mod) {}
    modint operator-() const { return modint(-x); }
    modint& operator+=(const modint& a){
        if(mod<=(x += a.x)) x-=mod;
        return *this;
    }
    modint& operator-=(const modint& a){
        if(mod<=(x+=mod-a.x)) x-=mod;
        return *this;
    }
    modint& operator*=(const modint& a){
        (x*=a.x)%=mod;
        return *this;
    }
    modint& operator++(){
        ++x;
        return *this;
    }
    modint operator++(int){
        modint temp = *this;
        x++;
        return temp;
    }
    modint& operator--(){
        --x;
        return *this;
    }
    modint operator--(int){
        modint temp = *this;
        x--;
        return temp;
    }
    modint pow(ll t) const{
        modint a=1,b=x;
        while(t){
            if(t&1) a*=b;
            b*=b;
            t/=2;
        }
        return a;
    }
    modint inv() const { return pow(mod-2); }
    modint& operator/=(const modint& a){ return (*this)*=a.inv(); }
    friend modint operator+(const modint& a, const modint& b) { return modint(a)+=b; }
    friend modint operator-(const modint& a, const modint& b) { return modint(a)-=b; }
    friend modint operator*(const modint& a, const modint& b) { return modint(a)*=b; }
    friend modint operator/(const modint& a, const modint& b) { return modint(a)/=b; }
    friend bool operator==(const modint& a, const modint& b) { return (modint(a).x==b.x); }
    friend bool operator!=(const modint& a, const modint& b) { return (modint(a).x!=b.x); }
    friend ostream& operator<<(ostream& os, const modint& m){ os << m.x; return os; }
    friend istream& operator>>(istream& is, modint& m){ is >> m.x; return is; }
};

using fp998=modint<998244353>;
using fp107=modint<1000000007>;

int main(){
    int n; cin >> n;
    vll d(n);
    rep(i,n-1){
        int a, b; cin >> a >> b;
        a--; b--;
        d[a]++; d[b]++;
    }
    sort(d); rev(d);

    fp998 ans = 0, t = 2;
    rep(i,n) ans += t.pow(d[i]);
    if(d[1]==1) ans -= 2;
    cout << ans << el;

}