#include "bits/stdc++.h" #define Rep(i,n) for(int i=0;i> a(n,vector(m,0)); using namespace std; typedef long long ll; typedef pair P; template inline bool chmax(T& a, T b) {if(a inline bool chmin(T& a, T b) {if(a>b){a=b;return 1;}return 0;} class Modulo{ public: ll val; static const ll mod = 1e9+7; vector factable = {1}; vector invtable = {1}; ll pro(ll x,ll y){return ((x%mod)*(y%mod))%mod;} ll sum(ll x,ll y){return ((x%mod)+(y%mod))%mod;} ll dif(ll x,ll y){ll d =((x%mod)-(y%mod))%mod;if(d>=0){return d;}else{return d+mod;}} ll quo(ll x, ll y){return pro(x,pow(y,mod-2));} ll pow(ll x,ll y){ if(y<=0){return 1;} if(y%2==0){ll d = pow(x,y/2);return ((d%mod)*(d%mod))%mod;} else{return (x*pow(x,y-1))%mod;} } void operator=(ll n){this->val = n%mod;} ll operator+(ll n){return sum(this->val,n);} ll operator-(ll n){return dif(this->val,n);} ll operator*(ll n){return pro(this->val,n);} ll operator/(ll n){return quo(this->val,n);} void operator+=(ll n){this->val = sum(this->val,n);} void operator-=(ll n){this->val = dif(this->val,n);} void operator*=(ll n){this->val = pro(this->val,n);} void operator/=(ll n){this->val = quo(this->val,n);} ll fac(ll x){ //x! mod mod if(factable.size()<=x){ ll s = factable.size(); FOR(i,s,x+1){ factable.push_back(pro(i,factable.back())); invtable.push_back(quo(1,factable.back())); } } if(x<0) return 1; else return factable[x]; } ll facinv(ll x){ if(invtable.size()<=x){ ll s = invtable.size(); FOR(i,s,x+1){ factable.push_back(pro(i,factable.back())); invtable.push_back(quo(1,factable.back())); } } if(x<0) return 1; else return invtable[x]; } ll com(ll x,ll y){ //xCy mod mod = x!/((x-y)!*y!) mod mod if(x-y> n; m=1; m=4*m.pow(10,n)-1; m/=3; put(m.val); return 0; }