#include #include using namespace std; using ll = long long int; const ll MOD = 1000'000'007; vector> update(vector> &matrix, ll mod){ vector> ans(matrix.size(), vector(matrix.size(), 0)); for(int i = 0; i < matrix.size(); i++){ for(int j = 0; j < matrix.size(); j++){ for(int k = 0; k < matrix.size(); k++){ ans[i][j] += matrix[i][k]*matrix[k][j]; ans[i][j] %= mod; } } } return ans; } vector times(vector &memo, vector> &matrix, ll mod){ vector ans(memo.size(), 0); for(int i = 0; i < memo.size(); i++){ for(int j = 0; j < memo.size(); j++){ ans[i] += memo[j]*matrix[i][j]; ans[i] %= mod; } } return ans; } vector matpow(vector &memo, vector> &matrix, ll n, ll mod){ vector ans = memo; while(n){ if(n & 1){ ans = times(ans, matrix, mod); } matrix = update(matrix, mod); n >>= 1; } return ans; } int main(){ ll n; cin >> n; vector> matrix(2, vector(2)); vector memo(2); matrix[0][0] = matrix[0][1] = matrix[1][0] = 1; matrix[1][1] = 0; memo[0] = 1; memo[1] = 0; memo = matpow(memo, matrix, n, (MOD+1)*2); ll fn = memo[1]; matrix[0][0] = matrix[0][1] = matrix[1][0] = 1; matrix[1][1] = 0; memo[0] = 1; memo[1] = 0; memo = matpow(memo, matrix, fn, MOD); cout << memo[1] << endl; return 0; }