#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- ll C[26]; string S; const ll mo=998244353; const int NUM_=1400001; static ll fact[NUM_+1],factr[NUM_+1],inv[NUM_+1]; ll modpow(ll a, ll n = mo-2) { ll r=1; while(n) r=r*((n%2)?a:1)%mo,a=a*a%mo,n>>=1; return r; } template vector fft(vector v, bool rev=false) { int n=v.size(),i,j,m; for(i=0,j=1;j>1;k>(i^=k);k>>=1); if(i>j) swap(v[i],v[j]); } for(int m=2; m<=n; m*=2) { T wn=modpow(5,(mo-1)/m); if(rev) wn=modpow(wn); for(i=0;i=mo) v[j1]-=mo; while(v[j2]>=mo) v[j2]-=mo; w=(ll)w*wn%mo; } } } if(rev) { ll rv = modpow(n); FOR(i,n) v[i]=(ll)v[i]*rv%mo; } return v; } template vector MultPoly(vector P,vector Q,bool resize=true) { if(resize) { int maxind=0,pi=0,qi=0,i; int s=2; FOR(i,P.size()) if(norm(P[i])) pi=i; FOR(i,Q.size()) if(norm(Q[i])) qi=i; maxind=pi+qi+1; while(s*2>S; FORR(c,S) C[c-'a']++; inv[1]=fact[0]=factr[0]=1; for (int i=2;i<=NUM_;++i) inv[i] = inv[mo % i] * (mo - mo / i) % mo; for (int i=1;i<=NUM_;++i) fact[i]=fact[i-1]*i%mo, factr[i]=factr[i-1]*inv[i]%mo; vector V(1<<20); V[0]=1; sort(C,C+26); FOR(i,26) if(C[i]) { vector W(C[i]+1); FOR(j,V.size()) V[j]=V[j]*factr[j]%mo; FOR(j,W.size()) W[j]=factr[j]; V=MultPoly(V,W,1); FOR(j,V.size()) V[j]=V[j]*fact[j]%mo; } ll ret=0; for(i=1;i<=S.size();i++) ret+=V[i]; cout<