結果

問題 No.1507 Road Blocked
ユーザー yuto1115yuto1115
提出日時 2021-04-13 19:44:48
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 37 ms / 2,000 ms
コード長 6,258 bytes
コンパイル時間 2,165 ms
コンパイル使用メモリ 211,160 KB
実行使用メモリ 11,904 KB
最終ジャッジ日時 2024-06-30 00:27:57
合計ジャッジ時間 5,256 ms
ジャッジサーバーID
（参考情報） 		judge4 / 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 1 ms
5,248 KB
testcase_01 AC 2 ms
5,376 KB
testcase_02 AC 1 ms
5,376 KB
testcase_03 AC 29 ms
11,904 KB
testcase_04 AC 35 ms
8,832 KB
testcase_05 AC 36 ms
8,960 KB
testcase_06 AC 35 ms
8,832 KB
testcase_07 AC 36 ms
8,960 KB
testcase_08 AC 36 ms
8,960 KB
testcase_09 AC 36 ms
8,960 KB
testcase_10 AC 37 ms
8,832 KB
testcase_11 AC 35 ms
8,960 KB
testcase_12 AC 35 ms
8,960 KB
testcase_13 AC 36 ms
8,832 KB
testcase_14 AC 36 ms
8,832 KB
testcase_15 AC 35 ms
8,832 KB
testcase_16 AC 35 ms
8,960 KB
testcase_17 AC 35 ms
8,960 KB
testcase_18 AC 35 ms
8,832 KB
testcase_19 AC 35 ms
8,832 KB
testcase_20 AC 37 ms
9,088 KB
testcase_21 AC 37 ms
8,960 KB
testcase_22 AC 37 ms
8,832 KB
testcase_23 AC 35 ms
8,960 KB
testcase_24 AC 35 ms
8,832 KB
testcase_25 AC 35 ms
8,960 KB
testcase_26 AC 35 ms
8,832 KB
testcase_27 AC 35 ms
8,960 KB
testcase_28 AC 34 ms
8,832 KB
testcase_29 AC 35 ms
8,832 KB
testcase_30 AC 35 ms
8,968 KB
testcase_31 AC 34 ms
8,832 KB
testcase_32 AC 35 ms
8,960 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 # 

//@formatter:off
#include<bits/stdc++.h>
#define overload4(_1,_2,_3,_4,name,...) name
#define rep1(i,n) for (ll i = 0; i < ll(n); ++i)
#define rep2(i,s,n) for (ll i = ll(s); i < ll(n); ++i)
#define rep3(i,s,n,d) for(ll i = ll(s); i < ll(n); i+=d)
#define rep(...) overload4(__VA_ARGS__,rep3,rep2,rep1)(__VA_ARGS__)
#define rrep1(i,n) for (ll i = ll(n)-1; i >= 0; i--)
#define rrep2(i,n,t) for (ll i = ll(n)-1; i >= (ll)t; i--)
#define rrep3(i,n,t,d) for (ll i = ll(n)-1; i >= (ll)t; i-=d)
#define rrep(...) overload4(__VA_ARGS__,rrep3,rrep2,rrep1)(__VA_ARGS__)
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define popcount(x) __builtin_popcountll(x)
#define pb push_back
#define eb emplace_back
#ifdef __LOCAL
#define debug(...) { cout << #__VA_ARGS__; cout << ": "; print(__VA_ARGS__); cout << flush; }
#else
#define debug(...) void(0)
#endif
#define INT(...) int __VA_ARGS__;scan(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;scan(__VA_ARGS__)
#define STR(...) string __VA_ARGS__;scan(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__;scan(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__;scan(__VA_ARGS__)
#define LD(...) ld __VA_ARGS__;scan(__VA_ARGS__)
using namespace std;
using ll = long long;
using ld = long double;
using P = pair<int,int>;
using LP = pair<ll,ll>;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
using vd = vector<double>;
using vvd = vector<vector<double>>;
using vs = vector<string>;
using vc = vector<char>;
using vvc = vector<vector<char>>;
using vb = vector<bool>;
using vvb = vector<vector<bool>>;
using vp = vector<P>;
using vvp = vector<vector<P>>;
template<class S,class T> istream& operator>>(istream &is,pair<S,T> &p) { return is >> p.first >> p.second; }
template<class S,class T> ostream& operator<<(ostream &os,const pair<S,T> &p) { return os<<'{'<<p.first<<","<<p.second<<'}'; }
template<class T> istream& operator>>(istream &is,vector<T> &v) { for(T &t:v){is>>t;} return is; }
template<class T> ostream& operator<<(ostream &os,const vector<T> &v) { os<<'[';rep(i,v.size())os<<v[i]<<(i==int(v.size()-1)?"":","); return os<<']'; }
template<class T> void vecout(const vector<T> &v,char div='\n') { rep(i,v.size()) cout<<v[i]<<(i==int(v.size()-1)?'\n':div);}
template<class T> bool chmin(T& a,T b) {if(a > b){a = b; return true;} return false;}
template<class T> bool chmax(T& a,T b) {if(a < b){a = b; return true;} return false;}
void scan(){}
template <class Head, class... Tail> void scan(Head& head, Tail&... tail){ cin >> head; scan(tail...); }
template<class T> void print(const T& t){ cout << t << '\n'; }
template <class Head, class... Tail> void print(const Head& head, const Tail&... tail){ cout<<head<<' '; print(tail...); }
template<class... T> void fin(const T&... a) { print(a...); exit(0); }
struct Init_io {
    Init_io() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
        cout.tie(nullptr);
        cout << boolalpha << fixed << setprecision(15);
    }
} init_io;
const string yes[] = {"no","yes"};
const string Yes[] = {"No","Yes"};
const string YES[] = {"NO","YES"};
const int inf = 1001001001;
const ll linf = 1001001001001001001;
//@formatter:on

template<int mod>
class modint {
    ll x;
public:
    constexpr modint(ll x = 0) : x((x % mod + mod) % mod) {}
    
    static constexpr int get_mod() { return mod; }
    
    constexpr int val() const { return x; }
    
    constexpr modint operator-() const { return modint(-x); }
    
    constexpr modint &operator+=(const modint &a) {
        if ((x += a.val()) >= mod) x -= mod;
        return *this;
    }
    
    constexpr modint &operator++() { return *this += 1; }
    
    constexpr modint &operator-=(const modint &a) {
        if ((x += mod - a.val()) >= mod) x -= mod;
        return *this;
    }
    
    constexpr modint &operator--() { return *this -= 1; }
    
    constexpr modint &operator*=(const modint &a) {
        (x *= a.val()) %= mod;
        return *this;
    }
    
    constexpr modint operator+(const modint &a) const {
        modint res(*this);
        return res += a;
    }
    
    constexpr modint operator-(const modint &a) const {
        modint res(*this);
        return res -= a;
    }
    
    constexpr modint operator*(const modint &a) const {
        modint res(*this);
        return res *= a;
    }
    
    constexpr modint pow(ll t) const {
        modint res = 1, a(*this);
        while (t > 0) {
            if (t & 1) res *= a;
            t >>= 1;
            a *= a;
        }
        return res;
    }
    
    // for prime mod
    constexpr modint inv() const { return pow(mod - 2); }
    
    constexpr modint &operator/=(const modint &a) { return *this *= a.inv(); }
    
    constexpr modint operator/(const modint &a) const {
        modint res(*this);
        return res /= a;
    }
};

using modint998244353 = modint<998244353>;
using modint1000000007 = modint<1000000007>;

template<int mod>
istream &operator>>(istream &is, modint<mod> &a) {
    ll x;
    is >> x;
    a = modint<mod>(x);
    return is;
}

template<int mod>
constexpr ostream &operator<<(ostream &os, const modint<mod> &a) { return os << a.val(); }

template<int mod>
constexpr bool operator==(const modint<mod> &a, const modint<mod> &b) { return a.val() == b.val(); }

template<int mod>
constexpr bool operator!=(const modint<mod> &a, const modint<mod> &b) { return a.val() != b.val(); }

template<int mod>
constexpr modint<mod> &operator++(modint<mod> &a) { return a += 1; }

template<int mod>
constexpr modint<mod> &operator--(modint<mod> &a) { return a -= 1; }

using mint = modint998244353;

using vm = vector<mint>;
using vvm = vector<vm>;

int main() {
    INT(n);
    vvi G(n);
    rep(i, n - 1) {
        INT(u, v);
        u--, v--;
        G[u].pb(v);
        G[v].pb(u);
    }
    mint ans = 0;
    auto dfs = [&](auto &dfs, int u, int p) -> int {
        int res = 1;
        for (int v : G[u]) {
            if (v == p) continue;
            int sz = dfs(dfs, v, u);
            res += sz;
            ans += ll(sz) * (sz - 1) / 2;
            ans += ll(n - sz) * (n - sz - 1) / 2;
        }
        return res;
    };
    dfs(dfs, 0, -1);
    ans /= ll(n) * (n - 1) / 2 * (n - 1);
    fin(ans);
}
0