結果
問題 | No.891 隣接3項間の漸化式 |
ユーザー |
|
提出日時 | 2020-08-04 19:30:16 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 3 ms / 2,000 ms |
コード長 | 5,530 bytes |
コンパイル時間 | 872 ms |
コンパイル使用メモリ | 69,456 KB |
最終ジャッジ日時 | 2025-01-12 14:23:16 |
ジャッジサーバーID (参考情報) |
judge5 / judge6 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 39 |
ソースコード
#include <iostream>#include <array>template <int MOD>struct ModInt {using lint = long long;int val;// constructorModInt(lint v = 0) : val(v % MOD) {if (val < 0) val += MOD;};// unary operatorModInt operator+() const { return ModInt(val); }ModInt operator-() const { return ModInt(MOD - val); }ModInt inv() const { return this->pow(MOD - 2); }// arithmeticModInt operator+(const ModInt& x) const { return ModInt(*this) += x; }ModInt operator-(const ModInt& x) const { return ModInt(*this) -= x; }ModInt operator*(const ModInt& x) const { return ModInt(*this) *= x; }ModInt operator/(const ModInt& x) const { return ModInt(*this) /= x; }ModInt pow(lint n) const {auto x = ModInt(1);auto b = *this;while (n > 0) {if (n & 1) x *= b;n >>= 1;b *= b;}return x;}// compound assignmentModInt& operator+=(const ModInt& x) {if ((val += x.val) >= MOD) val -= MOD;return *this;}ModInt& operator-=(const ModInt& x) {if ((val -= x.val) < 0) val += MOD;return *this;}ModInt& operator*=(const ModInt& x) {val = lint(val) * x.val % MOD;return *this;}ModInt& operator/=(const ModInt& x) { return *this *= x.inv(); }// comparebool operator==(const ModInt& b) const { return val == b.val; }bool operator!=(const ModInt& b) const { return val != b.val; }bool operator<(const ModInt& b) const { return val < b.val; }bool operator<=(const ModInt& b) const { return val <= b.val; }bool operator>(const ModInt& b) const { return val > b.val; }bool operator>=(const ModInt& b) const { return val >= b.val; }// I/Ofriend std::istream& operator>>(std::istream& is, ModInt& x) noexcept {lint v;is >> v;x = v;return is;}friend std::ostream& operator<<(std::ostream& os, const ModInt& x) noexcept { return os << x.val; }};template <class T, int D>struct Vector {using V = std::array<T, D>;V vec;// constructorVector() = default;Vector(T val) { vec.fill(val); }// getterT& operator[](int i) { return vec[i]; }T operator[](int i) const { return vec[i]; }typename V::iterator begin() { return vec.begin(); }typename V::iterator end() { return vec.end(); }// arithmeticVector operator+(const Vector& v) const { return Matrix(*this) += v; }Vector operator-(const Vector& v) const { return Matrix(*this) -= v; }T operator*(const Vector& v) const {T ret(0);for (int i = 0; i < D; ++i) ret += vec[i] * v[i];return ret;}// compound assignmentVector& operator+=(const Vector& v) {for (int i = 0; i < D; ++i) vec[i] += v[i];return *this;}Vector& operator-=(const Vector& v) {for (int i = 0; i < D; ++i) vec[i] -= v[i];return *this;}};template <class T, int D>struct Matrix {using M = std::array<std::array<T, D>, D>;M mat;// constructorMatrix() = default;Matrix(T val) {for (auto& v : mat) v.fill(val);}static Matrix id() {Matrix m;for (int i = 0; i < D; ++i) m[i][i] = 1;return m;}// getterstd::array<T, D>& operator[](int i) { return mat[i]; }std::array<T, D> operator[](int i) const { return mat[i]; }typename M::iterator begin() { return mat.begin(); }typename M::iterator end() { return mat.end(); }// arithmeticMatrix operator+(const Matrix& m) const { return Matrix(*this) += m; }Matrix operator-(const Matrix& m) const { return Matrix(*this) -= m; }Matrix operator*(const Matrix& m) const { return Matrix(*this) *= m; }template <class U>Matrix pow(U k) {Matrix ret = id();Matrix a = *this;while (k > 0) {if (k & 1) ret *= a;a *= a;k >>= 1;}return ret;}// compound assignmentMatrix& operator+=(const Matrix& m) {for (int i = 0; i < D; ++i) {for (int j = 0; j < D; ++j) {mat[i][j] += m[i][j];}}return *this;}Matrix& operator-=(const Matrix& m) {for (int i = 0; i < D; ++i) {for (int j = 0; j < D; ++j) {mat[i][j] -= m[i][j];}}return *this;}Matrix& operator*=(const Matrix& m) {M nmat;for (int i = 0; i < D; ++i) {for (int j = 0; j < D; ++j) {for (int k = 0; k < D; ++k) {nmat[i][j] += mat[i][k] * m[k][j];}}}mat = nmat;return *this;}// arithmetic with vectorusing Vec = Vector<T, D>;Vec operator*(const Vec& v) {Vec ret;for (int i = 0; i < D; ++i) {for (int j = 0; j < D; ++j) {ret[i] += mat[i][j] * v[j];}}return ret;}};constexpr int MOD = 1000000007;using mint = ModInt<MOD>;using Mat = Matrix<mint, 2>;void solve() {mint a, b;int n;std::cin >> a >> b >> n;Mat m;m[0][0] = a, m[0][1] = b, m[1][0] = 1;std::cout << (m.pow(n))[1][0] << "\n";}int main() {std::cin.tie(nullptr);std::ios::sync_with_stdio(false);solve();return 0;}