結果
問題 | No.1873 Bracket Swapping |
ユーザー |
|
提出日時 | 2021-12-16 21:42:32 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 266 ms / 2,000 ms |
コード長 | 3,897 bytes |
コンパイル時間 | 2,772 ms |
コンパイル使用メモリ | 214,388 KB |
最終ジャッジ日時 | 2025-01-26 23:48:07 |
ジャッジサーバーID (参考情報) |
judge4 / judge3 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 27 |
ソースコード
#include<bits/stdc++.h>typedef uint64_t u64;typedef int64_t i64;using namespace std;template<u64 mod> struct modint{u64 val;modint(i64 val_=0):val((val_%i64(mod)+i64(mod))%i64(mod)){}modint operator-(){return (val==0)?0:mod-val;}modint operator+(modint rhs){return modint(*this)+=rhs;}modint operator-(modint rhs){return modint(*this)-=rhs;}modint operator*(modint rhs){return modint(*this)*=rhs;}modint operator/(modint rhs){return modint(*this)/=rhs;}modint operator^(i64 rhs){return modint(*this)^=rhs;}modint &operator+=(modint rhs){val+=rhs.val,val-=((val>=mod)?mod:0);return (*this);}modint &operator-=(modint rhs){val+=((val<rhs.val)?mod:0),val-=rhs.val;return (*this);}modint &operator*=(modint rhs){val=val*rhs.val%mod;return (*this);}modint &operator/=(modint rhs){return (*this)*=rhs^(mod-2);}modint &operator^=(i64 rhs){modint res=1,now=(*this);while(rhs){res*=((rhs&1)?now:1),now*=now,rhs>>=1;}return (*this)=res;}bool operator==(modint rhs){return val==rhs.val;}bool operator!=(modint rhs){return val!=rhs.val;}friend std::ostream &operator<<(std::ostream& os,modint x){return os<<(x.val);}friend std::istream &operator>>(std::istream& is,modint& x){u64 t;is>>t,x=t;return is;}};template<typename T> struct matrix{vector<vector<T>> val;int height,width;matrix(int H,int W,T init=0):val(H,vector<T> (W,init)),height(H),width(W){}vector<T> &operator[](int i){return val[i];}matrix operator+(matrix rhs){return matrix(*this)+=rhs;}matrix operator*(matrix rhs){return matrix(*this)*=rhs;}matrix operator+=(matrix rhs){for(int i=0;i<rhs.height;++i){for(int j=0;j<rhs.width;++j){(*this)[i][j]+=rhs[i][j];}}return (*this);}matrix operator*=(matrix rhs){matrix<T> res(height,rhs.width,0);for(int i=0;i<this->height;++i){for(int j=0;j<rhs.width;++j){for(int k=0;k<this->width;++k){res[i][j]+=(*this)[i][k]*rhs[k][j];}}}return (*this)=res;}matrix identity(int n){matrix res(n,n);for(int i=0;i<n;++i){res[i][i]=1;}return res;}matrix pow(i64 k){int n=(*this).height;matrix res=identity(n),now=(*this);while(k>0){if(k%2==1){res*=now;}now*=now;k/=2;}return (*this)=res;}};template<typename T> struct comb{vector<T> dat,idat;comb(int mx=3000000):dat(mx+1,1),idat(mx+1,1){for(int i=1;i<=mx;++i){dat[i]=dat[i-1]*i;}idat[mx]/=dat[mx];for(int i=mx;i>0;--i){idat[i-1]=idat[i]*i;}}T operator()(int n,int k){if(n<0||k<0||n<k){return 0;}return dat[n]*idat[k]*idat[n-k];}};int main(){constexpr u64 mod=998244353;typedef modint<mod> mint;string S;int K;cin>>S>>K;int N=S.size()/2;vector<vector<vector<mint>>> dp(2*N+1,vector<vector<mint>> (2*N+5,vector<mint> (2*N+5)));dp[0][0][0]=1;for(int i=0;i<2*N;++i){for(int j=0;j<=2*N;++j){for(int k=0;k<=2*N;++k){if(S[i]=='('){dp[i+1][j+1][k]+=dp[i][j][k];if(0<j){dp[i+1][j-1][k+1]+=dp[i][j][k];}}else{dp[i+1][j+1][k+1]+=dp[i][j][k];if(0<j){dp[i+1][j-1][k]+=dp[i][j][k];}}}}}matrix<mint> A(N+1,N+1),B(N+1,1);B[0][0]=1;for(int i=0;i<=N;++i){A[i][i]=N*(2*N-1)-i*i-(N-i)*(N-i);if(0<i){A[i-1][i]=i*i;}if(i<N){A[i+1][i]=(N-i)*(N-i);}}B=A.pow(K)*B;mint ans=0;comb<mint> C;for(int i=0;i<=N;++i){ans+=dp[2*N][0][2*i]*B[i][0]/(C(N,i)^2);}cout<<ans<<endl;}