#include using namespace std; typedef long long ll; typedef pair P; long long int INF = 1e18; double Pi = 3.1415926535897932384626; //vector G[500005]; //vector

tree[500010]; priority_queue pql; priority_queue

pqp; //big priority queue priority_queue ,greater > pqls; priority_queue ,greater

> pqps; //small priority queue //top pop int dx[8]={1,0,-1,0,1,1,-1,-1}; int dy[8]={0,1,0,-1,1,-1,-1,1}; char dir[] = "DRUL"; //ll bit[500005]; //↓,→,↑,← #define p(x) cout< number2){ swap(number1,number2); } if(number1 == 0 || number1 == number2){ return number2; }else{ return gcd(number2 % number1,number1); } } void YES(bool condition){ if(condition){ p("YES"); }else{ p("NO"); } return; } void Yes(bool condition){ if(condition){ p("Yes"); }else{ p("No"); } return; } ll fact[800005],rfact[800005]; void c3_init(){ fact[0] = rfact[0] = 1; for(ll i=1; i<=800000; i++){ fact[i] = (fact[i-1]*i) % mod; } rfact[800000] = rui(fact[800000],mod - 2); for(ll i=800000; i>=1; i--){ rfact[i-1] = rfact[i] * i; rfact[i-1] %= mod; } return;} ll c3(ll n,ll r){ return (((fact[n] * rfact[r]) % mod) * rfact[n-r]) % mod;} ll n,m,num,sum,ans,a,b,c,e,g,h,w,i,j,k,q; ll t,d; ll x[500005],y[500005],z[500005]; ll large[100005],small[100005]; int main(){ cin >> n; c3_init(); ll a = n % mod; ll ans = (a - 2) * (a - 3); ans %= mod; ans *= rui(2ll, mod - 2); ans %= mod; if(n % 3 == 1){ ans -= 1; } ll same = (n - 2) / 2ll; if(n % 3 == 1){ same -= 1; } ans += mod - 3 * same; ans %= mod; ans *= rui(6ll, mod - 2); ans %= mod; ans += same; if(n % 3 == 1){ ans += 1; } ans %= mod; p(ans); return 0; }