include
include
using namespace std;
int mm = 1e9 + 7;
vector<vector<long long="">> matriMulti(vector<vector<long long="">> &m1,vector<vector<long long="">> &m2)
{</long></long></long>
int r=m1.size();
int c=m1[0].size();
vector<vector<long long>> res(r,vector<long long>(c,0));
for(int i=0;i<r;i++)
for(int j=0;j<c;j++)
for(int k=0;k<c;k++)
{
res[i][j]=(res[i][j]+(m1[i][k]*m2[k][j])%mm)%mm;
}
return res;}
void multi(vector<vector<long long="">> &res,vector<vector<long long="">> &m,long long n)
{</long></long>
res[0][0]=1;
res[0][1]=0;
res[0][2]=0;
res[1][0]=0;
res[1][1]=1;
res[1][2]=0;
res[2][0]=0;
res[2][1]=0;
res[2][2]=1;
vector<vector<long long>> mtemp=m;
while(n!=0)
{
if(n&1==1)
res=matriMulti(res,mtemp);
mtemp=matriMulti(mtemp,mtemp);
n=n>>1;
}}
long long f3(long long n)
{
if(n<1)
return 0;
if(n==1)
return 1;
if(n==2)
return 2;
if(n==3)
return 3;
vector<vector<long long>> m(3,vector<long long>(3,0)); vector<vector<long long>> res(3,vector<long long>(3,0)); m[0][0]=1; m[0][1]=1; m[0][2]=0; m[1][0]=0; m[1][1]=0; m[1][2]=1; m[2][0]=1; m[2][1]=0; m[2][2]=0; multi(res,m,n-3); return (3*res[0][0]+2*res[1][0]+res[2][0])%mm;
}
int main()
{
long long n; cin >> n; int result = f3(n); cout << result; return 0;
}

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