結果
問題 | No.1333 Squared Sum |
ユーザー |
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提出日時 | 2021-01-08 23:45:01 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
WA
|
実行時間 | - |
コード長 | 6,303 bytes |
コンパイル時間 | 1,222 ms |
コンパイル使用メモリ | 125,920 KB |
実行使用メモリ | 41,472 KB |
最終ジャッジ日時 | 2024-11-16 18:44:09 |
合計ジャッジ時間 | 10,440 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge2 |
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ファイルパターン | 結果 |
---|---|
other | AC * 9 WA * 35 |
ソースコード
#include <algorithm>#include <bitset>#include <cassert>#include <chrono>#include <climits>#include <cmath>#include <complex>#include <cstring>#include <deque>#include <functional>#include <iostream>#include <iomanip>#include <list>#include <map>#include <numeric>#include <queue>#include <random>#include <set>#include <stack>#include <unordered_map>#include <unordered_set>#include <vector>#include <cstdint>using namespace std;typedef long long ll;typedef vector<int> vi;typedef pair<int,int> pii;#define MP make_pair#define PB push_back#define inf 1000000007#define rep(i,n) for(int i = 0; i < (int)(n); ++i)#define all(x) (x).begin(),(x).end()template<typename A, size_t N, typename T>void Fill(A (&array)[N], const T &val){std::fill( (T*)array, (T*)(array+N), val );}template<class T> inline bool chmax(T &a, T b){if(a<b){a = b;return true;}return false;}template<class T> inline bool chmin(T &a, T b){if(a>b){a = b;return true;}return false;}template <unsigned int mod>class ModInt {private:unsigned int v;static unsigned int norm(const unsigned int& x){ return x < mod ? x : x - mod; }static ModInt make(const unsigned int& x){ ModInt m; return m.v = x, m; }static ModInt inv(const ModInt& x){ return make(inverse(x.v, mod)); }static unsigned int inverse(int a, int m){int u[] = {a, 1, 0}, v[] = {m, 0, 1}, t;while(*v){t = *u / *v;swap(u[0] -= t * v[0], v[0]), swap(u[1] -= t * v[1], v[1]), swap(u[2] -= t * v[2], v[2]);}return (u[1] % m + m) % m;}public:ModInt() : v{0}{}ModInt(const long long val) : v{norm(val % mod + mod)} {}ModInt(const ModInt<mod>& n) : v{n()} {}explicit operator bool() const noexcept { return v != 0; }bool operator!() const noexcept { return !static_cast<bool>(*this); }ModInt& operator=(const ModInt& n){ return v = n(), (*this); }ModInt& operator=(const long long val){ return v = norm(val % mod + mod), (*this); }ModInt operator+() const { return *this; }ModInt operator-() const { return v == 0 ? make(0) : make(mod - v); }ModInt operator+(const ModInt& val) const { return make(norm(v + val())); }ModInt operator-(const ModInt& val) const { return make(norm(v + mod - val())); }ModInt operator*(const ModInt& val) const { return make((long long)v * val() % mod); }ModInt operator/(const ModInt& val) const { return *this * inv(val); }ModInt& operator+=(const ModInt& val){ return *this = *this + val; }ModInt& operator-=(const ModInt& val){ return *this = *this - val; }ModInt& operator*=(const ModInt& val){ return *this = *this * val; }ModInt& operator/=(const ModInt& val){ return *this = *this / val; }ModInt operator+(const long long val) const { return ModInt{v + val}; }ModInt operator-(const long long val) const { return ModInt{v - val}; }ModInt operator*(const long long val) const { return ModInt{(long long)v * (val % mod)}; }ModInt operator/(const long long val) const { return ModInt{(long long)v * inv(val)}; }ModInt& operator+=(const long long val){ return *this = *this + val; }ModInt& operator-=(const long long val){ return *this = *this - val; }ModInt& operator*=(const long long val){ return *this = *this * val; }ModInt& operator/=(const long long val){ return *this = *this / val; }bool operator==(const ModInt& val) const { return v == val.v; }bool operator!=(const ModInt& val) const { return !(*this == val); }bool operator==(const long long val) const { return v == norm(val % mod + mod); }bool operator!=(const long long val) const { return !(*this == val); }unsigned int operator()() const { return v; }friend ModInt operator+(const long long val, const ModInt& n) { return n + val; }friend ModInt operator-(const long long val, const ModInt& n) { return ModInt{val - n()}; }friend ModInt operator*(const long long val, const ModInt& n) { return n * val; }friend ModInt operator/(const long long val, const ModInt& n) { return ModInt{val} / n; }friend bool operator==(const long long val, const ModInt& n) { return n == val; }friend bool operator!=(const long long val, const ModInt& n) { return !(val == n); }friend istream& operator>>(istream& is, ModInt& n){unsigned int v;return is >> v, n = v, is;}friend ostream& operator<<(ostream& os, const ModInt& n){ return (os << n()); }friend ModInt mod_pow(ModInt x, long long n){ModInt ans = 1;while(n){if(n & 1) ans *= x;x *= x, n >>= 1;}return ans;}};#define MOD 1000000007using mod = ModInt<MOD>;#define MAX_N 200000mod inv[MAX_N],fac[MAX_N],finv[MAX_N];void make(){fac[0] = fac[1] = 1;finv[0] = finv[1] = 1;inv[1] = 1;for(int i=2;i<MAX_N;i++){inv[i] = MOD - inv[MOD % i] * (MOD / i);fac[i] = fac[i-1] * i;finv[i] = finv[i-1] * inv[i];}}mod comb(int a, int b){if(a<b) return 0;return fac[a] * finv[b] * finv[a-b];}vector<vector<pair<int,mod> > > g;vector<mod> d2,d,cnt,res;void dfs(int id,int pre){for(auto x:g[id]){if(x.first!=pre){dfs(x.first,id);}}for(auto x:g[id]){if(x.first==pre)continue;mod P = x.second;int nxt = x.first;res[id] += d[id] * (d[nxt]+P*cnt[nxt]) * 2;res[id] += d2[id]*cnt[nxt] + cnt[id]*d2[nxt];d2[id] += P*2*d[nxt];d2[id] += cnt[nxt]*P*P;d2[id] += d2[nxt];d[id] += d[nxt] + cnt[nxt]*P;cnt[id] += cnt[nxt];}res[id] += d2[id];cnt[id]+=1;}int main(){int n;cin >> n;g.resize(n);d.resize(n);d2.resize(n);cnt.resize(n);res.resize(n);rep(i,n-1){int a,b,c;cin >> a >> b >> c;a--;b--;g[a].push_back(MP(b,c));g[b].push_back(MP(a,c));}dfs(0,-1);mod ans = 0;rep(i,n){ans += res[i];// cerr << i << ": " << d[i] << " " << d2[i] << " " << cnt[i] << " " << res[i] << endl;}cout << ans << endl;return 0;}