結果
問題 | No.1227 I hate ThREE |
ユーザー |
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提出日時 | 2020-09-12 00:43:20 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 62 ms / 2,000 ms |
コード長 | 6,066 bytes |
コンパイル時間 | 2,051 ms |
コンパイル使用メモリ | 199,904 KB |
最終ジャッジ日時 | 2025-01-14 12:35:06 |
ジャッジサーバーID (参考情報) |
judge3 / judge3 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 33 |
ソースコード
#include <bits/stdc++.h> using namespace std; #define LOCAL #pragma region Macros typedef long long ll; #define ALL(x) (x).begin(),(x).end() const long long MOD=1000000007; // const long long MOD=998244353; const int INF=1e9; const long long IINF=1e18; const int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1}; const char dir[4]={'D','R','U','L'}; template<typename T> istream &operator>>(istream &is,vector<T> &v){ for (T &x:v) is >> x; return is; } template<typename T> ostream &operator<<(ostream &os,const vector<T> &v){ for (int i=0;i<v.size();++i){ os << v[i] << (i+1==v.size()?"": " "); } return os; } template<typename T,typename U> ostream &operator<<(ostream &os,const pair<T,U> &p){ os << '(' << p.first << ',' << p.second << ')'; return os; } template<typename T,typename U> ostream &operator<<(ostream &os,const map<T,U> &m){ os << '{'; for (auto itr=m.begin();itr!=m.end();++itr){ os << '(' << itr->first << ',' << itr->second << ')'; if (++itr!=m.end()) os << ','; --itr; } os << '}'; return os; } template<typename T> ostream &operator<<(ostream &os,const set<T> &s){ os << '{'; for (auto itr=s.begin();itr!=s.end();++itr){ os << *itr; if (++itr!=s.end()) os << ','; --itr; } os << '}'; return os; } void debug_out(){cerr << '\n';} template<class Head,class... Tail> void debug_out(Head&& head,Tail&&... tail){ cerr << head; if (sizeof...(Tail)>0) cerr << ", "; debug_out(move(tail)...); } #ifdef LOCAL #define debug(...) cerr << " ";\ cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << '\n';\ cerr << " ";\ debug_out(__VA_ARGS__) #else #define debug(...) 42 #endif template<typename T> T gcd(T x,T y){return y!=0?gcd(y,x%y):x;} template<typename T> T lcm(T x,T y){return x/gcd(x,y)*y;} template<class T1,class T2> inline bool chmin(T1 &a,T2 b){ if (a>b){a=b; return true;} return false; } template<class T1,class T2> inline bool chmax(T1 &a,T2 b){ if (a<b){a=b; return true;} return false; } #pragma endregion template<uint_fast64_t Modulus> class modint{ using u64=uint_fast64_t; public: u64 a; constexpr modint(const u64 x=0) noexcept:a(x%Modulus){} constexpr u64 &value() noexcept{return a;} constexpr const u64 &value() const noexcept{return a;} constexpr modint &operator+=(const modint &rhs) noexcept{ a+=rhs.a; if (a>=Modulus) a-=Modulus; return *this; } constexpr modint operator+(const modint &rhs) const noexcept{ return modint(*this)+=rhs; } constexpr modint &operator++() noexcept{ return ++a,*this; } constexpr modint operator++(int) noexcept{ modint t=*this; return ++a,t; } constexpr modint &operator-=(const modint &rhs) noexcept{ if (a<rhs.a) a+=Modulus; a-=rhs.a; return *this; } constexpr modint operator-(const modint &rhs) const noexcept{ return modint(*this)-=rhs; } constexpr modint &operator--() noexcept{ return --a,*this; } constexpr modint operator--(int) noexcept{ modint t=*this; return --a,t; } constexpr modint &operator*=(const modint &rhs) noexcept{ a=a*rhs.a%Modulus; return *this; } constexpr modint operator*(const modint &rhs) const noexcept{ return modint(*this)*=rhs; } constexpr modint &operator/=(modint rhs) noexcept{ u64 exp=Modulus-2; while(exp){ if (exp&1) *this*=rhs; rhs*=rhs; exp>>=1; } return *this; } constexpr modint operator/(const modint &rhs) const noexcept{ return modint(*this)/=rhs; } constexpr modint operator-() const noexcept{ return modint(Modulus-a); } constexpr bool operator==(const modint &rhs) const noexcept{ return a==rhs.a; } constexpr bool operator!=(const modint &rhs) const noexcept{ return a!=rhs.a; } constexpr bool operator!() const noexcept{return !a;} friend constexpr modint pow(modint rhs,long long exp) noexcept{ modint res{1}; while(exp){ if (exp&1) res*=rhs; rhs*=rhs; exp>>=1; } return res; } template<class T> friend constexpr modint operator+(T x,modint y) noexcept{ return modint(x)+y; } template<class T> friend constexpr modint operator-(T x,modint y) noexcept{ return modint(x)-y; } template<class T> friend constexpr modint operator*(T x,modint y) noexcept{ return modint(x)*y; } template<class T> friend constexpr modint operator/(T x,modint y) noexcept{ return modint(x)/y; } friend ostream &operator<<(ostream &s,const modint &rhs) noexcept{ return s << rhs.a; } friend istream &operator>>(istream &s,modint &rhs) noexcept{ u64 a; rhs=modint{(s >> a,a)}; return s; } }; using mint=modint<MOD>; int main(){ cin.tie(0); ios::sync_with_stdio(false); int N,C; cin >> N >> C; vector<vector<int>> G(N); for (int i=0;i<N-1;++i){ int a,b; cin >> a >> b; --a,--b; G[a].emplace_back(b); G[b].emplace_back(a); } int MAX; auto dfs=[&](auto self,int v,int p)->vector<mint>{ vector<mint> dp(MAX,1); for (int u:G[v]){ if (u==p) continue; auto cdp=self(self,u,v); for (int i=0;i<MAX;++i){ mint sum=0; for (int j=-3;j<=3;j+=6){ int ni=i+j; if (ni<0||MAX<=ni) continue; sum+=cdp[ni]; } dp[i]*=sum; } } return dp; }; mint ans=0; if (C<6010){ MAX=C; vector<mint> dp=dfs(dfs,0,-1); for (int i=0;i<MAX;++i) ans+=dp[i]; } else { MAX=6010; vector<mint> dp=dfs(dfs,0,-1); for (int i=0;i<MAX;++i) ans+=dp[i]; ans+=pow((mint)2,N-1)*(C-6010); } cout << ans << '\n'; }