結果
問題 | No.1227 I hate ThREE |
ユーザー |
![]() |
提出日時 | 2020-09-11 22:02:06 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 410 ms / 2,000 ms |
コード長 | 8,009 bytes |
コンパイル時間 | 2,256 ms |
コンパイル使用メモリ | 216,948 KB |
最終ジャッジ日時 | 2025-01-14 10:30:44 |
ジャッジサーバーID (参考情報) |
judge1 / judge1 |
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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
#line 1 "code.cpp"#define MOD 1000000007LL//#define MOD 998244353LL//#define MOD 18446744069414584321ULL#include<bits/stdc++.h>#line 1 "cpplib/util/template.hpp"#pragma GCC optimize("Ofast")#pragma GCC optimize("unroll-loops")#pragma GCC target("avx")#line 5 "cpplib/util/template.hpp"using namespace std;__attribute__((constructor))void init(){cin.tie(0);ios::sync_with_stdio(false);cout<<fixed<<setprecision(15);}typedef long long lint;#define INF (1LL<<60)#define IINF (1<<30)#define EPS (1e-10)#define endl ('\n')typedef vector<lint> vec;typedef vector<vector<lint>> mat;typedef vector<vector<vector<lint>>> mat3;typedef vector<string> svec;typedef vector<vector<string>> smat;template<typename T>inline void numout(T t){bool f=0;for(auto i:t){cout<<(f?" ":"")<<i<INF/2?i:"INF";f=1;}cout<<endl;}template<typename T>inline void numout2(T t){for(auto i:t)numout(i);}template<typename T>inline void output(T t){bool f=0;for(auto i:t){cout<<(f?" ":"")<<i;f=1;}cout<<endl;}template<typename T>inline void output2(T t){for(auto i:t)output(i);}template<typename T>inline void _output(T t){bool f=0;for(lint i=0;i<t.size();i++){cout<<f?"":" "<<t[i];f=1;}cout<<endl;}template<typename T>inline void _output2(T t){for(lint i=0;i<t.size();i++)output(t[i]);}#define rep(i,...) for(auto i:range(__VA_ARGS__))#define rrep(i,...) for(auto i:reversed(range(__VA_ARGS__)))#define repi(i,a,b) for(lint i=lint(a);i<(lint)(b);++i)#define rrepi(i,a,b) for(lint i=lint(b)-1;i>=lint(a);--i)#define irep(i) for(lint i=0;;++i)inline vector<long long> range(long long n){vector<long long>v(n);iota(v.begin(),v.end(),0LL);return v;}inline vector<long long> range(long long a,long long b){vector<long long>v(b-a);iota(v.begin(),v.end(),a);return v;}inline vector<long long> range(long long a,long long b,long long c){if((b-a+c-1)/c<=0)return vector<long long>();vector<long long>v((b-a+c-1)/c);for(int i=0;i<(int)v.size();++i)v[i]=i?v[i-1]+c:a;return v;}template<typename T>inline T reversed(T v){reverse(v.begin(),v.end());return v;}#define all(n) begin(n),end(n)#define dist(a,b,c,d) sqrt(pow(a-c,2)+pow(b-d,2))template<typename T,typename E>bool chmin(T& s,const E& t){bool res=s>t;s=min<T>(s,t);return res;}template<typename T,typename E>bool chmax(T& s,const E& t){bool res=s<t;s=max<T>(s,t);return res;}const vector<lint> dx={1,0,-1,0,1,1,-1,-1};const vector<lint> dy={0,1,0,-1,1,-1,1,-1};#define SUM(v) accumulate(all(v),0LL)template<typename T,typename ...Args>auto make_vector(T x,int arg,Args ...args){if constexpr(sizeof...(args)==0)return vector<T>(arg,x);else returnvector(arg,make_vector<T>(x,args...));}#line 1 "cpplib/math/mod_int.hpp"class mint {using u64 = std::uint_fast64_t;public:u64 a;constexpr mint(const long long x = 0)noexcept:a(x>=0?x%get_mod():get_mod()-(-x)%get_mod()){}constexpr u64 &value()noexcept{return a;}constexpr const u64 &value() const noexcept {return a;}constexpr mint operator+(const mint rhs)const noexcept{return mint(*this) += rhs;}constexpr mint operator-(const mint rhs)const noexcept{return mint(*this)-=rhs;}constexpr mint operator*(const mint rhs) const noexcept {return mint(*this) *= rhs;}constexpr mint operator/(const mint rhs) const noexcept {return mint(*this) /= rhs;}constexpr mint &operator+=(const mint rhs) noexcept {a += rhs.a;if (a >= get_mod())a -= get_mod();return *this;}constexpr mint &operator-=(const mint rhs) noexcept {if (a<rhs.a)a += get_mod();a -= rhs.a;return *this;}constexpr mint &operator*=(const mint rhs) noexcept {a = a * rhs.a % get_mod();return *this;}constexpr mint operator++(int) noexcept {a += 1;if (a >= get_mod())a -= get_mod();return *this;}constexpr mint operator--(int) noexcept {if (a<1)a += get_mod();a -= 1;return *this;}constexpr mint &operator/=(mint rhs) noexcept {u64 exp=get_mod()-2;while (exp) {if (exp % 2) {*this *= rhs;}rhs *= rhs;exp /= 2;}return *this;}constexpr bool operator==(mint x) noexcept {return a==x.a;}constexpr bool operator!=(mint x) noexcept {return a!=x.a;}constexpr bool operator<(mint x) noexcept {return a<x.a;}constexpr bool operator>(mint x) noexcept {return a>x.a;}constexpr bool operator<=(mint x) noexcept {return a<=x.a;}constexpr bool operator>=(mint x) noexcept {return a>=x.a;}constexpr static int root(){mint root = 2;while(root.pow((get_mod()-1)>>1).a==1)root++;return root.a;}constexpr mint pow(long long n){long long x=a;mint ret = 1;while(n>0) {if(n&1)(ret*=x);(x*=x)%=get_mod();n>>=1;}return ret;}constexpr mint inv(){return pow(get_mod()-2);}static vector<mint> fac,ifac;static bool init;constexpr static int mx=10000001;void build(){init=0;fac.resize(mx);ifac.resize(mx);fac[0]=1,ifac[0]=1;for(int i=1;i<mx;i++)fac[i]=fac[i-1]*i;ifac[mx-1]=fac[mx-1].inv();for(int i=mx-2;i>=0;i--)ifac[i]=ifac[i+1]*(i+1);}mint comb(long long b){if(init)build();if(a==0&&b==0)return 1;if((long long)a<b)return 0;return fac[a]*ifac[a-b]*ifac[b];}mint fact(){if(init)build();return fac[a];}mint fact_inv(){if(init)build();return ifac[a];}friend ostream& operator<<(ostream& lhs, const mint& rhs) noexcept {lhs << rhs.a;return lhs;}friend istream& operator>>(istream& lhs,mint& rhs) noexcept {lhs >> rhs.a;return lhs;}constexpr static u64 get_mod(){return MOD;}};vector<mint> mint::fac;vector<mint> mint::ifac;bool mint::init=1;#line 1 "cpplib/data_structure/dsu/union_find.hpp"/*** @brief Union Find* @docs docs/union_find.md* @see https://ja.wikipedia.org/wiki/%E7%B4%A0%E9%9B%86%E5%90%88%E3%83%87%E3%83%BC%E3%82%BF%E6%A7%8B%E9%80%A0*/class UF{public:vector<int> data;int sz;public:UF(int sz):sz(sz){data.resize(sz,-1);}bool unite(int x,int y){x=root(x);y=root(y);if(x==y)return 0;if(data[x]>data[y])swap(x,y);data[x]+=data[y];data[y]=x;sz--;return 1;}inline int root(int x){return data[x]<0?x:data[x]=root(data[x]);}inline bool same(int x, int y){return root(x)==root(y);}inline int size(){return sz;}inline int size(int x){return -data[root(x)];}};#line 8 "code.cpp"int main(){lint n,c;cin>>n>>c;mat g(n);rep(i,n-1){lint s,t;cin>>s>>t;s--;t--;g[s].push_back(t);g[t].push_back(s);}auto memo=make_vector<lint>(-1,n,min(8*n,c)+1);auto f=[&](auto f,lint now,lint p,lint val)->lint{if(memo[now][val]!=-1)return memo[now][val];mint ans=1;for(lint e:g[now]){if(p==e)continue;mint tmp=0;if(val-3>=0)tmp+=f(f,e,now,val-3);if(val+3<c)tmp+=f(f,e,now,val+3);ans*=tmp;}return memo[now][val]=ans.a;};if(4*n>=c){mint ans2=0;rep(i,c){ans2+=f(f,0,-1,i);}cout<<ans2<<endl;return 0;}vec ans(min(4*n,c));rep(i,min(4*n,c)){ans[i]=f(f,0,-1,i);}mint ans2=0;set<lint>used;rep(i,4*n){used.insert(i);ans2+=ans[min(i,c-i)];}rep(i,4*n){if(used.count(c-i))continue;used.insert(c-i);ans2+=ans[min(c-i,i)];}cout<<ans2+mint(c-used.size())*ans.back()<<endl;}