#include #include #include #include #include #include #include #include #include #include #define mkp make_pair #define mkt make_tuple #define rep(i,n) for(int i = 0; i < (n); ++i) #define all(v) v.begin(),v.end() using namespace std; typedef long long ll; const ll MOD=998244353; template void chmin(T &a,const T &b){if(a>b) a=b;} template void chmax(T &a,const T &b){if(a0){ if(n&1) res=res*x%MOD; x=x*x%MOD; n>>=1; } return res; } ll mod_inverse(ll x){ return mod_pow(x,MOD-2); } void add(ll &a,ll b){ a=(a+b)%MOD; } void mul(ll &a,ll b){ a%=MOD;b%=MOD; a=a*b%MOD; } //const ll MOD=998244353; // MOD == 119*2^23+1 //depends on mod_pow,mod_inverse ll root[24],invroot[24]; void NTT_init(){ for(int i=0;i<24;i++){ root[i]=mod_pow(3,(MOD-1)/(1< NTT(vector a,bool inverse=false){ int n=a.size(); int high=0; for(int i=0;(1<>k&1) mask|=(1<<(high-1-k)); } if(i=MOD) a[k]-=MOD; a[k+m/2]=s-t+MOD; while(a[k+m/2]>=MOD) a[k+m/2]-=MOD; (powzeta*=zeta)%=MOD; } } } if(inverse){ ll invn=mod_inverse(n); for(int i=0;i convolute(const vector &a,const vector &b){ int size=a.size()+b.size()-1; int n=1; while(n A(n,0),B(n,0); for(int i=0;i>S; int N=S.size(); vector alp(26,0); rep(i,N) alp[S[i]-'a']++; sort(all(alp)); setComb(); NTT_init(); vector ans={1}; vector A={1}; for(int k=0;k<26;k++){ if(alp[k]==0) continue; while(A.size()<=alp[k]){ int sz=A.size(); A.push_back(ifac[sz]); } ans=convolute(ans,A); } for(int i=0;i