結果
問題 | No.916 Encounter On A Tree |
ユーザー |
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提出日時 | 2019-10-25 22:56:03 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 28 ms / 2,000 ms |
コード長 | 5,224 bytes |
コンパイル時間 | 2,421 ms |
コンパイル使用メモリ | 198,904 KB |
最終ジャッジ日時 | 2025-01-08 01:35:19 |
ジャッジサーバーID (参考情報) |
judge4 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 5 |
other | AC * 56 |
ソースコード
#include<bits/stdc++.h>using namespace std;using Int = long long;template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}template<typename T,T MOD = 1000000007>struct Mint{static constexpr T mod = MOD;T v;Mint():v(0){}Mint(signed v):v(v){}Mint(long long t){v=t%MOD;if(v<0) v+=MOD;}Mint pow(long long k){Mint res(1),tmp(v);while(k){if(k&1) res*=tmp;tmp*=tmp;k>>=1;}return res;}static Mint add_identity(){return Mint(0);}static Mint mul_identity(){return Mint(1);}Mint inv(){return pow(MOD-2);}Mint& operator+=(Mint a){v+=a.v;if(v>=MOD)v-=MOD;return *this;}Mint& operator-=(Mint a){v+=MOD-a.v;if(v>=MOD)v-=MOD;return *this;}Mint& operator*=(Mint a){v=1LL*v*a.v%MOD;return *this;}Mint& operator/=(Mint a){return (*this)*=a.inv();}Mint operator+(Mint a) const{return Mint(v)+=a;};Mint operator-(Mint a) const{return Mint(v)-=a;};Mint operator*(Mint a) const{return Mint(v)*=a;};Mint operator/(Mint a) const{return Mint(v)/=a;};Mint operator-() const{return v?Mint(MOD-v):Mint(v);}bool operator==(const Mint a)const{return v==a.v;}bool operator!=(const Mint a)const{return v!=a.v;}bool operator <(const Mint a)const{return v <a.v;}static Mint comb(long long n,Int k){Mint num(1),dom(1);for(Int i=0;i<k;i++){num*=Mint(n-i);dom*=Mint(i+1);}return num/dom;}};template<typename T,T MOD> constexpr T Mint<T, MOD>::mod;template<typename T,T MOD>ostream& operator<<(ostream &os,Mint<T, MOD> m){os<<m.v;return os;}template<typename T> void drop(const T &x){cout<<x<<endl;exit(0);}template<typename M>class Enumeration{private:static vector<M> fact,finv,invs;public:static void init(Int n){n=min<decltype(M::mod)>(n,M::mod-1);Int m=fact.size();if(n<m) return;fact.resize(n+1,1);finv.resize(n+1,1);invs.resize(n+1,1);if(m==0) m=1;for(Int i=m;i<=n;i++) fact[i]=fact[i-1]*M(i);finv[n]=M(1)/fact[n];for(Int i=n;i>=m;i--) finv[i-1]=finv[i]*M(i);for(Int i=m;i<=n;i++) invs[i]=finv[i]*fact[i-1];}static M Fact(Int n){init(n);return fact[n];}static M Finv(Int n){init(n);return finv[n];}static M Invs(Int n){init(n);return invs[n];}static M C(Int n,Int k){if(n<k||k<0) return M(0);init(n);return fact[n]*finv[n-k]*finv[k];}static M P(Int n,Int k){if(n<k||k<0) return M(0);init(n);return fact[n]*finv[n-k];}static M H(Int n,Int k){if(n<0||k<0) return M(0);if(!n&&!k) return M(1);init(n+k-1);return C(n+k-1,k);}static M S(Int n,Int k){init(k);M res(0);for(Int i=1;i<=k;i++){M tmp=C(k,i)*M(i).pow(n);if((k-i)&1) res-=tmp;else res+=tmp;}return res*=finv[k];}static vector< vector<M> > D(Int n,Int m){vector< vector<M> > dp(n+1,vector<M>(m+1,0));dp[0][0]=M(1);for(Int i=0;i<=n;i++){for(Int j=1;j<=m;j++){if(i-j>=0) dp[i][j]=dp[i][j-1]+dp[i-j][j];else dp[i][j]=dp[i][j-1];}}return dp;}static M B(Int n,Int k){if(n==0) return M(1);k=min(k,n);init(k);vector<M> dp(k+1);dp[0]=M(1);for(Int i=1;i<=k;i++)dp[i]=dp[i-1]+((i&1)?-finv[i]:finv[i]);M res(0);for(Int i=1;i<=k;i++)res+=M(i).pow(n)*finv[i]*dp[k-i];return res;}static M montmort(Int n){init(n);M res(0);for(Int k=2;k<=n;k++){if(k&1) res-=finv[k];else res+=finv[k];}return res*=fact[n];}static M LagrangePolynomial(vector<M> &y,M t){Int n=y.size()-1;if(t.v<=n) return y[t.v];init(n+1);vector<M> dp(n+1,1),pd(n+1,1);for(Int i=0;i<n;i++) dp[i+1]=dp[i]*(t-M(i));for(Int i=n;i>0;i--) pd[i-1]=pd[i]*(t-M(i));M res(0);for(Int i=0;i<=n;i++){M tmp=y[i]*dp[i]*pd[i]*finv[i]*finv[n-i];if((n-i)&1) res-=tmp;else res+=tmp;}return res;}};template<typename M>vector<M> Enumeration<M>::fact=vector<M>();template<typename M>vector<M> Enumeration<M>::finv=vector<M>();template<typename M>vector<M> Enumeration<M>::invs=vector<M>();//INSERT ABOVE HEREsigned main(){Int d,l,r,k;cin>>d>>l>>r>>k;auto dep=[&](Int v){Int c=0;while(v) v>>=1,c++;return c;};Int x=dep(l),y=dep(r);assert(1<=x&&x<=d);assert(1<=y&&y<=d);if(x+y<k) drop(0);if((x+y-k)&1) drop(0);using M = Mint<Int>;using E = Enumeration<M>;// lcaif(y-x==k){M ans{1};for(Int i=1;i<=d;i++){Int len=(1<<(i-1))-(i==x);ans*=E::Fact(len);}cout<<ans<<endl;return 0;}Int z=(x+y-k)/2;if(z<=0||x<=z) drop(0);//cout<<x<<" "<<y<<" "<<z<<endl;if(x==y){M ans=M(2).pow(x-1+y-z-1);for(Int i=1;i<=d;i++){Int len=(1<<(i-1));if(i==y) len-=2;ans*=E::Fact(len);}cout<<ans<<endl;return 0;}M ans=M(2).pow(y-z-1);for(Int i=1;i<=d;i++){Int len=(1<<(i-1))-(i==y);ans*=E::Fact(len);}cout<<ans<<endl;return 0;}