#include using namespace std; using Int = long long; template inline void chmin(T1 &a,T2 b){if(a>b) a=b;} template inline void chmax(T1 &a,T2 b){if(a struct Mint{ 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; } 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-(){return v?MOD-v: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 dp; dp.reserve(sq); Mint res(1); for(int r=0;r0) return idx; } res*=p; } return T(-1); } static vector fact,finv,invs; static void init(int n){ if(n+1<=(signed)fact.size()) return; fact.assign(n+1,1); finv.assign(n+1,1); invs.assign(n+1,1); for(int i=1;i<=n;i++) fact[i]=fact[i-1]*Mint(i); finv[n]=Mint(1)/fact[n]; for(int i=n;i>=1;i--) finv[i-1]=finv[i]*Mint(i); for(int i=1;i<=n;i++) invs[i]=finv[i]*fact[i-1]; } static Mint comb(long long n,int k){ Mint res(1); for(int i=0;i > D(int n,int m){ vector > dp(n+1,vector(m+1,0)); dp[0][0]=Mint(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 Mint B(int n,int k){ Mint res; for(int j=1;j<=k;j++) res+=S(n,j); return res; } static Mint montmort(int n){ Mint res; init(n); for(int k=2;k<=n;k++){ if(k&1) res-=finv[k]; else res+=finv[k]; } return res*=fact[n]; } static Mint LagrangePolynomial(vector &y,Mint t){ int n=y.size()-1; if(t.v<=n) return y[t.v]; init(n+1); Mint num(1); for(int i=0;i<=n;i++) num*=t-Mint(i); Mint res; for(int i=0;i<=n;i++){ Mint tmp=y[i]*num/(t-Mint(i))*finv[i]*finv[n-i]; if((n-i)&1) res-=tmp; else res+=tmp; } return res; } }; template vector > Mint::fact = vector >(); template vector > Mint::finv = vector >(); template vector > Mint::invs = vector >(); //INSERT ABOVE HERE signed main(){ using M = Mint; int n; cin>>n; vector a(n); for(int i=0;i>a[i]; M::init(n*2); M ans=0; for(int i=0;i