#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace atcoder; using namespace std; using ll=long long; using ull=unsigned long long; using P=pair; templateusing minque=priority_queue,greater>; templatebool chmax(T &a,const T &b){return (abool chmin(T &a,const T &b){return (a>b?(a=b,true):false);} template ostream &operator<<(ostream &os,const pair&p){ os< istream &operator>>(istream &is,pair&p){ is>>p.first>>p.second; return is; } template istream &operator>>(istream &is,vector &a){ for(auto &i:a)is>>i; return is; } #define reps(i,a,n) for(int i=(a);i<(n);i++) #define rep(i,n) reps(i,0,n) #define all(x) x.begin(),x.end() ll myceil(ll a,ll b){return (a+b-1)/b;} using mint=modint1000000007; int main(){ int n; cin>>n; vector>dp(n+1,vector(10,0)); dp[0][0]=1; rep(i,n){ rep(j,10){ reps(k,j,10){ dp[i+1][k]+=dp[i][j]; } } } mint ans=0; rep(i,10)ans+=dp[n][i]; cout<