#include #include #include using namespace atcoder; using mint = modint1000000007; using namespace std; #define rep(i,n) for (int i = 0; i < (n); ++i) #define Inf 100000000001 template vector convolution_mint(vector a,vector b){ static constexpr unsigned long long M0 = 998244353; static constexpr unsigned long long M1 = 754974721; static constexpr unsigned long long M2 = 469762049; vector aa(a.size()),bb(b.size()); rep(i,a.size())aa[i] = a[i].val(); rep(i,b.size())bb[i] = b[i].val(); auto c0 = convolution(aa,bb); auto c1 = convolution(aa,bb); auto c2 = convolution(aa,bb); vector ret(c0.size()); vector m = {M0,M1,M2}; rep(i,c0.size()){ ret[i] += c0[i]; { long long cur = c0[i]; cur %= M1; cur = c1[i]-cur; if(cur<0)cur += M1; cur *= 416537774; cur %= M1; mint m = M0; ret[i] += m*cur; cur *= M0; cur += c0[i]; cur %= M2; cur = c2[i] - cur; if(cur<0)cur += M2; cur *= 429847628; cur %= M2; m *= M1; ret[i] += m * cur; } } return ret; } vector mul(vector a,vector b){ /* vector c(a.size()+b.size()-1,0); rep(i,a.size()){ rep(j,b.size()){ c[i+j] += a[i]*b[j]; } } return c; */ return convolution_mint(a,b); } //first a[0],a[1],... //nxt c[0]*a[i-1]+c[1]*a[i-2]+... mint Bostan_Mori(vector a,vector c,long long n){ int d = c.size(); rep(i,c.size()){ c[i] *= -1; } c.insert(c.begin(),1); a.insert(a.begin(),0); a = mul(a,c); while(a.size()>1+d)a.pop_back(); while(n!=0){ auto cinv = c; for(int i=1;i na; for(int i=(n&1LL);i nc; for(int i=0;i>=1; } return a[0] / c[0]; } int main(){ long long N,K; cin>>N>>K; vector c(N,1); vector a(N); rep(i,N){ int t; cin>>t; a[i] = t; } cout<