結果
| 問題 | No.1333 Squared Sum |
| ユーザー |
👑  tute7627
|
| 提出日時 | 2021-01-08 22:08:53 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 1,289 ms / 2,000 ms |
| コード長 | 12,224 bytes |
| コンパイル時間 | 3,151 ms |
| コンパイル使用メモリ | 223,196 KB |
| 最終ジャッジ日時 | 2025-01-17 12:17:26 |
|
ジャッジサーバーID （参考情報） |
judge3 / judge4 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 44 |
ソースコード
//#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;}template<typename T>ostream &operator<<(ostream &os, const vector<T> &v){for(auto &z:v)os << z << " ";cout<<"|"; return os;}//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());int popcount(ll x){return __builtin_popcountll(x);};int poplow(ll x){return __builtin_ctzll(x);};int pophigh(ll x){return 63 - __builtin_clzll(x);};template< typename Monoid, typename OperatorMonoid,typename F, typename G, typename H>struct LazySegmentTree {ll sz, height, n;vector< Monoid > data;vector< OperatorMonoid > lazy;const F f;const G g;const H h;Monoid M1;OperatorMonoid OM0;LazySegmentTree(ll n, const F &f,const G &g, const H &h, Monoid M1, OperatorMonoid OM0):n(n),f(f),g(g),h(h),M1(M1),OM0(OM0){sz = 1;height = 0;while(sz < n) sz <<= 1, height++;data.assign(2 * sz, M1);lazy.assign(2 * sz, OM0);}void set(ll k, const Monoid &x) {data[k + sz] = x;}void build() {for(ll k = sz - 1; k > 0; k--) {data[k] = f(data[2 * k + 0], data[2 * k + 1]);}}inline void propagate(ll k) {if(lazy[k] != OM0) {lazy[2 * k + 0] = h(lazy[2 * k + 0], lazy[k]);lazy[2 * k + 1] = h(lazy[2 * k + 1], lazy[k]);data[k] = reflect(k);lazy[k] = OM0;}}inline Monoid reflect(ll k) {return lazy[k] == OM0 ? data[k] : g(data[k], lazy[k]);}inline void recalc(ll k) {while(k >>= 1) data[k] = f(reflect(2 * k + 0), reflect(2 * k + 1));}inline void thrust(ll k) {for(ll i = height; i > 0; i--) propagate(k >> i);}void update(ll a, ll b, const OperatorMonoid &x) {if(a>=b)return;thrust(a += sz);thrust(b += sz - 1);for(ll l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {if(l & 1) lazy[l] = h(lazy[l], x), ++l;if(r & 1) --r, lazy[r] = h(lazy[r], x);}recalc(a);recalc(b);}Monoid query(ll a, ll b) {thrust(a += sz);thrust(b += sz - 1);Monoid L = M1, R = M1;for(ll l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {if(l & 1) L = f(L, reflect(l++));if(r & 1) R = f(reflect(--r), R);}return f(L, R);}Monoid operator[](const ll &k) {return query(k, k + 1);}template< typename C >ll find_subtree(ll a, const C &check, Monoid &M, bool type) {while(a < sz) {propagate(a);Monoid nxt = type ? f(reflect(2 * a + type), M) : f(M, reflect(2 * a + type));if(check(nxt)) a = 2 * a + type;else M = nxt, a = 2 * a + 1 - type;}return a - sz;}template< typename C >ll find_first(ll a, const C &check) {Monoid L = M1;if(a <= 0) {if(check(f(L, reflect(1)))) return find_subtree(1, check, L, false);return -1;}thrust(a + sz);ll b = sz;for(a += sz, b += sz; a < b; a >>= 1, b >>= 1) {if(a & 1) {Monoid nxt = f(L, reflect(a));if(check(nxt)) return find_subtree(a, check, L, false);L = nxt;++a;}}return -1;}template< typename C >ll find_last(ll b, const C &check) {Monoid R = M1;if(b >= sz) {if(check(f(reflect(1), R))) return find_subtree(1, check, R, true);return -1;}thrust(b + sz - 1);ll a = sz;for(b += sz; a < b; a >>= 1, b >>= 1) {if(b & 1) {Monoid nxt = f(reflect(--b), R);if(check(nxt)) return find_subtree(b, check, R, true);R = nxt;}}return -1;}void print(){for(ll i=0;i<n;i++)if((*this)[i]==M1)cout<<"x|";else cout<<(*this)[i]<<"|";cout<<endl;}};struct edge{ll to=-1,cost=0;edge(){};edge(ll t,ll c):to(t),cost(c){};};struct HLD{ll n, root;ll cnt = 0;vector<ll>sz;//部分木サイズvector<ll>par,head;vector<vector<struct edge>>g;//隣接リストvector<struct edge>edges;//データ構造に乗せるedge列vector<ll>in,out;//[in,out)で部分木、[ina,inb]でa~bのパス(aが上)//inは頂点のindexを表す。また、edge列の下側の頂点であるHLD(vector<vector<struct edge>>&G,ll r = -1):g(G),n(G.size()),root(r){par.assign(n,-1),in.assign(n,-1);out.assign(n,-1),head.assign(n,-1),sz.assign(n,-1);edges.assign(n,edge());dfs_build();}void dfs_build(){if(root == -1){//根がどこでも良い場合(森でも可)for(ll i=0;i<n;i++){if(sz[i] == -1){head[i] = i;dfs_sz(i);dfs_hld(i);}}}else{head[root] = root;dfs_sz(root);dfs_hld(root);}}void dfs_sz(ll k){sz[k] = 1;for(auto &e: g[k]){if(e.to == par[k])continue;par[e.to] = k;dfs_sz(e.to);sz[k] += sz[e.to];if(sz[e.to] > sz[g[k][0].to])swap(e, g[k][0]);}}void dfs_hld(ll k){in[k] = cnt++;for(auto e:g[k]){if(e.to == par[k])continue;head[e.to] = (e.to == g[k][0].to ? head[k]: e.to);edges[cnt] = e;dfs_hld(e.to);}out[k] = cnt;}ll lca(ll p,ll q){while(1){if(in[p] < in[q])swap(p,q);if(head[p] == head[q])return q;p = par[head[p]];}}vector<pair<ll,ll>>query_path(ll p,ll q,bool isEdge){ll r=lca(p,q);vector<pair<ll,ll>>ret;for(ll i=0;i<2;i++){if(i == 1)swap(p,q);while(1){if(isEdge&&p==r)break;if(head[p]==head[r]){ret.emplace_back(in[r]+(isEdge?1:i),in[p]+1);break;}ret.emplace_back(in[head[p]],in[p]+1);p = par[head[p]];}}return ret;}vector<vector<pair<ll,ll>>>query_order_path(ll p,ll q,bool isEdge){//非可換クエリ用、配列0を順番を反転したデータ構造に、配列1を通常のデータ構造にvector<vector<pair<ll,ll>>>ret(2);ll r=lca(p,q);for(ll i=0;i<2;i++){if(i == 1)swap(p,q);while(1){if(isEdge&&p==r)break;if(head[p]==head[r]){if(i==0) ret[i].emplace_back(n-(in[p]+1),n-(in[r]+(isEdge?1:i)));else ret[i].emplace_back(in[r]+(isEdge?1:i),in[p]+1);break;}if(i==0) ret[i].emplace_back(n-(in[p]+1),n-(in[head[p]]));else ret[i].emplace_back(in[head[p]],in[p]+1);p = par[head[p]];}}reverse(ret[1].begin(), ret[1].end());return ret;}pair<ll,ll>query_subtree(ll p,bool isEdge){return make_pair(in[p]+isEdge,out[p]);}//uのv方向の子 子孫関係は前もって確認することll child(ll u,ll v){while(1){if(head[u]==head[v]){v=g[u][0].to;break;}v=head[v];if(par[v]==u)break;v=par[v];}return v;}};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); }friend ModInt operator+(const ModInt& lhs, const ModInt& rhs) {return ModInt(lhs) += rhs;}friend ModInt operator-(const ModInt& lhs, const ModInt& rhs) {return ModInt(lhs) -= rhs;}friend ModInt operator*(const ModInt& lhs, const ModInt& rhs) {return ModInt(lhs) *= rhs;}friend ModInt operator/(const ModInt& lhs, const ModInt& rhs) {return ModInt(lhs) /= rhs;}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;int main(){cin.tie(nullptr);ios_base::sync_with_stdio(false);ll res=0,buf=0;bool judge = true;using A=array<modint,3>;auto f=[&](A x,A y){return A({x[0]+y[0],x[1]+y[1],x[2]+y[2]});};auto gg=[&](A x,modint y){return A({x[0]+2*x[1]*y+y*y*x[2],x[1]+x[2]*y,x[2]});};auto h=[&](modint x,modint y){return x+y;};ll n;cin>>n;LazySegmentTree seg(n,f,gg,h,A({0,0,0}),modint(0));vector<vector<edge>>g(n);rep(i,0,n-1){ll a,b,c;cin>>a>>b>>c;a--;b--;g[a].EB(b,c);g[b].EB(a,c);}HLD hld(g,0);modint ret=0;{auto dfs=[&](auto &&f,ll k,ll par,ll d)->void{seg.set(hld.in[k],A({modint(d)*d,d,1}));for(auto e:g[k]){if(par==e.to)continue;f(f,e.to,k,d+e.cost);}};dfs(dfs,0,0,0);}seg.build();//rep(i,0,n)cout<<seg[i][0] spa seg[i][1] spa seg[i][2]<<endl;{auto sub=[&](ll k){auto tmp=hld.query_subtree(k,false);return seg.query(tmp.fi,tmp.se)[0];};auto subadd=[&](ll k,modint x){auto tmp=hld.query_subtree(k,false);seg.update(tmp.fi,tmp.se,x);};auto dfs=[&](auto &&f,ll k,ll par)->void{ret+=sub(0);for(auto e:g[k]){if(e.to==par)continue;subadd(0,e.cost);subadd(e.to,-2*e.cost);f(f,e.to,k);subadd(0,-e.cost);subadd(e.to,2*e.cost);}};dfs(dfs,0,-1);}//rep(i,0,n)cout<<seg[i][0] spa seg[i][1] spa seg[i][2]<<endl;cout<<ret/2<<endl;return 0;}