結果

問題 No.1103 Directed Length Sum
ユーザー 👑 tute7627tute7627
提出日時 2020-07-03 21:52:49
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 810 ms / 3,000 ms
コード長 5,140 bytes
コンパイル時間 2,386 ms
コンパイル使用メモリ 218,952 KB
実行使用メモリ 109,452 KB
最終ジャッジ日時 2024-09-17 00:22:36
合計ジャッジ時間 9,896 ms
ジャッジサーバーID
(参考情報)
judge6 / judge1
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
5,248 KB
testcase_01 AC 2 ms
5,376 KB
testcase_02 AC 322 ms
109,452 KB
testcase_03 AC 192 ms
66,092 KB
testcase_04 AC 447 ms
40,028 KB
testcase_05 AC 810 ms
66,944 KB
testcase_06 AC 222 ms
27,196 KB
testcase_07 AC 37 ms
8,960 KB
testcase_08 AC 57 ms
11,904 KB
testcase_09 AC 22 ms
6,912 KB
testcase_10 AC 85 ms
15,232 KB
testcase_11 AC 492 ms
43,364 KB
testcase_12 AC 250 ms
27,392 KB
testcase_13 AC 91 ms
15,616 KB
testcase_14 AC 18 ms
5,888 KB
testcase_15 AC 204 ms
22,016 KB
testcase_16 AC 572 ms
48,384 KB
testcase_17 AC 603 ms
50,176 KB
testcase_18 AC 98 ms
15,232 KB
testcase_19 AC 513 ms
44,288 KB
testcase_20 AC 29 ms
7,680 KB
testcase_21 AC 54 ms
11,136 KB
testcase_22 AC 412 ms
36,736 KB
testcase_23 AC 214 ms
23,276 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 #

//#define _GLIBCXX_DEBUG

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

#define endl '\n'
#define lfs cout<<fixed<<setprecision(10)
#define ALL(a)  (a).begin(),(a).end()
#define ALLR(a)  (a).rbegin(),(a).rend()
#define spa << " " <<
#define fi first
#define se second
#define MP make_pair
#define MT make_tuple
#define PB push_back
#define EB emplace_back
#define rep(i,n,m) for(ll i = (n); i < (ll)(m); i++)
#define rrep(i,n,m) for(ll i = (ll)(m) - 1; i >= (ll)(n); i--)
using ll = long long;
using ld = long double;
const ll MOD1 = 1e9+7;
const ll MOD9 = 998244353;
const ll INF = 1e18;
using P = pair<ll, ll>;
template<typename T1, typename T2>
bool chmin(T1 &a,T2 b){if(a>b){a=b;return true;}else return false;}
template<typename T1, typename T2>
bool chmax(T1 &a,T2 b){if(a<b){a=b;return true;}else return false;}
ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});}
void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;}
void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;}
void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;}
template<typename T1,typename T2>
void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;}  
template<typename T>
void debug(vector<vector<T>>&v,ll h,ll w){for(ll i=0;i<h;i++)
{cout<<v[i][0];for(ll j=1;j<w;j++)cout spa v[i][j];cout<<endl;}};
void debug(vector<string>&v,ll h,ll w){for(ll i=0;i<h;i++)
{for(ll j=0;j<w;j++)cout<<v[i][j];cout<<endl;}};
template<typename T>
void debug(vector<T>&v,ll n){if(n!=0)cout<<v[0];
for(ll i=1;i<n;i++)cout spa v[i];cout<<endl;};
template<typename T>
vector<vector<T>>vec(ll x, ll y, T w){
  vector<vector<T>>v(x,vector<T>(y,w));return v;}
ll gcd(ll x,ll y){ll r;while(y!=0&&(r=x%y)!=0){x=y;y=r;}return y==0?x:y;}
vector<ll>dx={1,-1,0,0,1,1,-1,-1};
vector<ll>dy={0,0,1,-1,1,-1,1,-1};
template<typename T>
vector<T> make_v(size_t a,T b){return vector<T>(a,b);}
template<typename... Ts>
auto make_v(size_t a,Ts... ts){
  return vector<decltype(make_v(ts...))>(a,make_v(ts...));
}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2>&p){
  return os << p.first << " " << p.second;
}
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());
template< int mod >
struct ModInt {
  int x;

  ModInt() : x(0) {}

  ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}

  ModInt &operator+=(const ModInt &p) {
    if((x += p.x) >= mod) x -= mod;
    return *this;
  }

  ModInt &operator-=(const ModInt &p) {
    if((x += mod - p.x) >= mod) x -= mod;
    return *this;
  }

  ModInt &operator*=(const ModInt &p) {
    x = (int) (1LL * x * p.x % mod);
    return *this;
  }

  ModInt &operator/=(const ModInt &p) {
    *this *= p.inverse();
    return *this;
  }

  ModInt operator-() const { return ModInt(-x); }

  ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }

  ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }

  ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }

  ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }

  bool operator==(const ModInt &p) const { return x == p.x; }

  bool operator!=(const ModInt &p) const { return x != p.x; }

  ModInt inverse() const {
    int a = x, b = mod, u = 1, v = 0, t;
    while(b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return ModInt(u);
  }

  ModInt pow(int64_t n) const {
    ModInt ret(1), mul(x);
    while(n > 0) {
      if(n & 1) ret *= mul;
      mul *= mul;
      n >>= 1;
    }
    return ret;
  }

  friend ostream &operator<<(ostream &os, const ModInt &p) {
    return os << p.x;
  }

  friend istream &operator>>(istream &is, ModInt &a) {
    int64_t t;
    is >> t;
    a = ModInt< mod >(t);
    return (is);
  }

  static int get_mod() { return mod; }
};
using modint = ModInt< MOD1 >;modint pow(ll n, ll x){return modint(n).pow(x);}modint pow(modint n, ll x){return n.pow(x);}
//using modint=ld;
vector<ll>tsort(vector<vector<ll>>&g){
  ll n = g.size();
  vector<ll>ret(n),ret2(n);
  vector<ll>v(n);
  for(ll i=0;i<n;i++)for(ll j=0;j<g[i].size();j++)v[g[i][j]]++;
  stack<ll>st;
  for(ll i=0;i<n;i++)if(v[i]==0)st.push(i);
  for(ll i=0;i<n;i++){
    if(st.empty())return vector<ll>();//閉路がある
    ll x=st.top();
    st.pop();
    ret[x]=i;
    ret2[i]=x;
    for(ll j=0;j<g[x].size();j++){
      v[g[x][j]]--;
      if(v[g[x][j]]==0)st.push(g[x][j]);
    }
  }
  //ret:頂点のトポロジカル順序の割り当て ret2:頂点をトポロジカル順に並べたもの
  return ret2;
}
int main(){
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  ll res=0,buf=0;
  bool judge = true;
  ll n;cin>>n;
  vector<vector<ll>>g(n);
  rep(i,0,n-1){
    ll a,b;cin>>a>>b;a--;b--;
    g[a].PB(b);
  }
  auto v=tsort(g);
  modint ret=0;
  vector<modint>sz(n,1);
  auto dfs=[&](auto &&f,ll k,ll d)->void{
    for(auto to:g[k]){
      f(f,to,d+1);
      //cout<<k spa to spa sz[k] spa sz[to]<<endl;
      sz[k]+=sz[to];
      ret+=sz[to]*d;
    }
  };
  //cout<<v[0]<<endl;
  dfs(dfs,v[0],1);
  //debug(sz,n);
  cout<<ret<<endl;
  return 0;
}
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