結果
問題 | No.1559 Next Rational |
ユーザー | 👑 tute7627 |
提出日時 | 2021-06-25 22:48:57 |
言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
結果 |
AC
|
実行時間 | 2 ms / 2,000 ms |
コード長 | 20,978 bytes |
コンパイル時間 | 2,716 ms |
コンパイル使用メモリ | 219,872 KB |
実行使用メモリ | 6,944 KB |
最終ジャッジ日時 | 2024-06-25 08:43:35 |
合計ジャッジ時間 | 3,285 ms |
ジャッジサーバーID (参考情報) |
judge1 / judge4 |
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テストケース
テストケース表示入力 | 結果 | 実行時間 実行使用メモリ |
---|---|---|
testcase_00 | AC | 2 ms
6,812 KB |
testcase_01 | AC | 2 ms
6,944 KB |
testcase_02 | AC | 2 ms
6,944 KB |
testcase_03 | AC | 2 ms
6,944 KB |
testcase_04 | AC | 2 ms
6,940 KB |
testcase_05 | AC | 2 ms
6,940 KB |
testcase_06 | AC | 2 ms
6,940 KB |
testcase_07 | AC | 2 ms
6,940 KB |
testcase_08 | AC | 2 ms
6,940 KB |
testcase_09 | AC | 2 ms
6,944 KB |
testcase_10 | AC | 2 ms
6,940 KB |
testcase_11 | AC | 2 ms
6,944 KB |
testcase_12 | AC | 2 ms
6,944 KB |
testcase_13 | AC | 2 ms
6,940 KB |
testcase_14 | AC | 2 ms
6,940 KB |
testcase_15 | AC | 2 ms
6,940 KB |
testcase_16 | AC | 2 ms
6,944 KB |
testcase_17 | AC | 2 ms
6,944 KB |
ソースコード
//#define _GLIBCXX_DEBUG #include<bits/stdc++.h> using namespace std; #define endl '\n' #define lfs cout<<fixed<<setprecision(10) #define ALL(a) (a).begin(),(a).end() #define ALLR(a) (a).rbegin(),(a).rend() #define spa << " " << #define fi first #define se second #define MP make_pair #define MT make_tuple #define PB push_back #define EB emplace_back #define rep(i,n,m) for(ll i = (n); i < (ll)(m); i++) #define rrep(i,n,m) for(ll i = (ll)(m) - 1; i >= (ll)(n); i--) using ll = long long; using ld = long double; const ll MOD1 = 1e9+7; const ll MOD9 = 998244353; const ll INF = 1e18; using P = pair<ll, ll>; template<typename T> using PQ = priority_queue<T>; template<typename T> using QP = priority_queue<T,vector<T>,greater<T>>; template<typename T1, typename T2>bool chmin(T1 &a,T2 b){if(a>b){a=b;return true;}else return false;} template<typename T1, typename T2>bool chmax(T1 &a,T2 b){if(a<b){a=b;return true;}else return false;} ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});} void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;} void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;} void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;} template<typename T1,typename T2>void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;} template<typename T1,typename T2,typename T3>void anss(T1 x,T2 y,T3 z){ans(x!=y,x,z);}; template<typename T>void debug(const T &v,ll h,ll w,string sv=" "){for(ll i=0;i<h;i++){cout<<v[i][0];for(ll j=1;j<w;j++)cout<<sv<<v[i][j];cout<<endl;}}; template<typename T>void debug(const T &v,ll n,string sv=" "){if(n!=0)cout<<v[0];for(ll i=1;i<n;i++)cout<<sv<<v[i];cout<<endl;}; template<typename T>void debug(const vector<T>&v){debug(v,v.size());} template<typename T>void debug(const vector<vector<T>>&v){for(auto &vv:v)debug(vv,vv.size());} template<typename T>void debug(stack<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;} template<typename T>void debug(queue<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop();}cout<<endl;} template<typename T>void debug(deque<T> st){while(!st.empty()){cout<<st.front()<<" ";st.pop_front();}cout<<endl;} template<typename T>void debug(PQ<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;} template<typename T>void debug(QP<T> st){while(!st.empty()){cout<<st.top()<<" ";st.pop();}cout<<endl;} template<typename T>void debug(const set<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;} template<typename T>void debug(const multiset<T>&v){for(auto z:v)cout<<z<<" ";cout<<endl;} template<typename T,typename V>void debug(const map<T,V>&v){for(auto z:v)cout<<"["<<z.first<<"]="<<z.second<<",";cout<<endl;} template<typename T>vector<vector<T>>vec(ll x, ll y, T w){vector<vector<T>>v(x,vector<T>(y,w));return v;} ll gcd(ll x,ll y){ll r;while(y!=0&&(r=x%y)!=0){x=y;y=r;}return y==0?x:y;} vector<ll>dx={1,-1,0,0,1,1,-1,-1};vector<ll>dy={0,0,1,-1,1,-1,1,-1}; template<typename T>vector<T> make_v(size_t a,T b){return vector<T>(a,b);} template<typename... Ts>auto make_v(size_t a,Ts... ts){return vector<decltype(make_v(ts...))>(a,make_v(ts...));} template<typename T1, typename T2>ostream &operator<<(ostream &os, const pair<T1, T2>&p){return os << p.first << " " << p.second;} template<typename T>ostream &operator<<(ostream &os, const vector<T> &v){for(auto &z:v)os << z << " ";cout<<"|"; return os;} template<typename T>void rearrange(vector<int>&ord, vector<T>&v){ auto tmp = v; for(int i=0;i<tmp.size();i++)v[i] = tmp[ord[i]]; } template<typename Head, typename... Tail>void rearrange(vector<int>&ord,Head&& head, Tail&&... tail){ rearrange(ord, head); rearrange(ord, tail...); } template<typename T> vector<int> ascend(const vector<T>&v){ vector<int>ord(v.size());iota(ord.begin(),ord.end(),0); sort(ord.begin(),ord.end(),[&](int i,int j){return v[i]<v[j];}); return ord; } template<typename T> vector<int> descend(const vector<T>&v){ vector<int>ord(v.size());iota(ord.begin(),ord.end(),0); sort(ord.begin(),ord.end(),[&](int i,int j){return v[i]>v[j];}); return ord; } ll FLOOR(ll n,ll div){return n>=0?n/div:(n-div+1)/div;} ll CEIL(ll n,ll div){return n>=0?(n+div-1)/div:n/div;} ll digitsum(ll n){ll ret=0;while(n){ret+=n%10;n/=10;}return ret;} template<typename T>T min(const vector<T>&v){return *min_element(v.begin(),v.end());} template<typename T>T max(const vector<T>&v){return *max_element(v.begin(),v.end());} template<typename T>T acc(const vector<T>&v){return accumulate(v.begin(),v.end(),T(0));}; template<typename T>T reverse(const T &v){return T(v.rbegin(),v.rend());}; //mt19937 mt(chrono::steady_clock::now().time_since_epoch().count()); int popcount(ll x){return __builtin_popcountll(x);}; int poplow(ll x){return __builtin_ctzll(x);}; int pophigh(ll x){return 63 - __builtin_clzll(x);}; template<typename T>T poll(queue<T> &q){auto ret=q.front();q.pop();return ret;}; template<typename T>T poll(priority_queue<T> &q){auto ret=q.top();q.pop();return ret;}; template<typename T>T poll(QP<T> &q){auto ret=q.top();q.pop();return ret;}; template<typename T>T poll(stack<T> &s){auto ret=s.top();s.pop();return ret;}; template< typename T = int > struct edge { int to; T cost; int id; edge():id(-1){}; edge(int to, T cost = 1, int id = -1):to(to), cost(cost), id(id){} operator int() const { return to; } }; template<typename T> using Graph = vector<vector<edge<T>>>; template<typename T> Graph<T>revgraph(const Graph<T> &g){ Graph<T>ret(g.size()); for(int i=0;i<g.size();i++){ for(auto e:g[i]){ int to = e.to; e.to = i; ret[to].push_back(e); } } return ret; } template<typename T> Graph<T> readGraph(int n,int m,int indexed=1,bool directed=false,bool weighted=false){ Graph<T> ret(n); for(int es = 0; es < m; es++){ int u,v; T w=1; cin>>u>>v;u-=indexed,v-=indexed; if(weighted)cin>>w; ret[u].emplace_back(v,w,es); if(!directed)ret[v].emplace_back(u,w,es); } return ret; } template<typename T> Graph<T> readParent(int n,int indexed=1,bool directed=true){ Graph<T>ret(n); for(int i=1;i<n;i++){ int p;cin>>p; p-=indexed; ret[p].emplace_back(i); if(!directed)ret[i].emplace_back(p); } return ret; } template< typename T > struct FormalPowerSeries : vector< T > { using vector< T >::vector; using P = FormalPowerSeries; using MULT = function< P(P, P) >; using FFT = function< void(P &) >; using SQRT = function< T(T) >; static MULT &get_mult() { static MULT mult = nullptr; return mult; } static void set_mult(MULT f) { get_mult() = f; } static FFT &get_fft() { static FFT fft = nullptr; return fft; } static FFT &get_ifft() { static FFT ifft = nullptr; return ifft; } static void set_fft(FFT f, FFT g) { get_fft() = f; get_ifft() = g; } static SQRT &get_sqrt() { static SQRT sqr = nullptr; return sqr; } static void set_sqrt(SQRT sqr) { get_sqrt() = sqr; } void shrink() { while(this->size() && this->back() == T(0)) this->pop_back(); } P operator+(const P &r) const { return P(*this) += r; } P operator+(const T &v) const { return P(*this) += v; } P operator-(const P &r) const { return P(*this) -= r; } P operator-(const T &v) const { return P(*this) -= v; } P operator*(const P &r) const { return P(*this) *= r; } P operator*(const T &v) const { return P(*this) *= v; } P operator/(const P &r) const { return P(*this) /= r; } P operator%(const P &r) const { return P(*this) %= r; } P &operator+=(const P &r) { if(r.size() > this->size()) this->resize(r.size()); for(int i = 0; i < r.size(); i++) (*this)[i] += r[i]; return *this; } P &operator+=(const T &r) { if(this->empty()) this->resize(1); (*this)[0] += r; return *this; } P &operator-=(const P &r) { if(r.size() > this->size()) this->resize(r.size()); for(int i = 0; i < r.size(); i++) (*this)[i] -= r[i]; //shrink(); return *this; } P &operator-=(const T &r) { if(this->empty()) this->resize(1); (*this)[0] -= r; //shrink(); return *this; } P &operator*=(const T &v) { const int n = (int) this->size(); for(int k = 0; k < n; k++) (*this)[k] *= v; return *this; } P &operator*=(const P &r) { if(this->empty() || r.empty()) { this->clear(); return *this; } if(min(this->size(), r.size()) < 5 || get_mult() == nullptr){ P ret(this->size() + r.size() - 1); for(int i = 0; i < this->size(); i++){ for(int j = 0; j < r.size(); j++){ ret[i + j] += (*this)[i] * r[j]; } } return *this = ret; } return *this = get_mult()(*this, r); } P &operator%=(const P &r) { return *this -= *this / r * r; } P operator-() const { P ret(this->size()); for(int i = 0; i < this->size(); i++) ret[i] = -(*this)[i]; return ret; } P &operator/=(const P &r) { if(this->size() < r.size()) { this->clear(); return *this; } int n = this->size() - r.size() + 1; return *this = (rev().pre(n) * r.rev().inv(n)).pre(n).rev(n); } P dot(P r) const { P ret(min(this->size(), r.size())); for(int i = 0; i < ret.size(); i++) ret[i] = (*this)[i] * r[i]; return ret; } P pre(int sz) const { return P(begin(*this), begin(*this) + min((int) this->size(), sz)); } P operator>>(int sz) const { if(this->size() <= sz) return {}; P ret(*this); ret.erase(ret.begin(), ret.begin() + sz); return ret; } P operator<<(int sz) const { P ret(*this); ret.insert(ret.begin(), sz, T(0)); return ret; } P rev(int deg = -1) const { P ret(*this); if(deg != -1) ret.resize(deg, T(0)); reverse(begin(ret), end(ret)); return ret; } P diff() const { const int n = (int) this->size(); P ret(max(0, n - 1)); for(int i = 1; i < n; i++) ret[i - 1] = (*this)[i] * T(i); return ret; } P integral() const { const int n = (int) this->size(); P ret(n + 1); ret[0] = T(0); for(int i = 0; i < n; i++) ret[i + 1] = (*this)[i] / T(i + 1); return ret; } // F(0) must not be 0 P inv(int deg = -1) const { assert(((*this)[0]) != T(0)); const int n = (int) this->size(); if(deg == -1) deg = n; if(get_fft() != nullptr) { P ret(*this); ret.resize(deg, T(0)); return ret.inv_fast(); } P ret({T(1) / (*this)[0]}); for(int i = 1; i < deg; i <<= 1) { ret = (ret + ret - ret * ret * pre(i << 1)).pre(i << 1); } return ret.pre(deg); } // F(0) must be 1 P log(int deg = -1) const { assert((*this)[0] == 1); const int n = (int) this->size(); if(deg == -1) deg = n; return (this->diff() * this->inv(deg)).pre(deg - 1).integral(); } P sqrt(int deg = -1) const { const int n = (int) this->size(); if(deg == -1) deg = n; if((*this)[0] == T(0)) { for(int i = 1; i < n; i++) { if((*this)[i] != T(0)) { if(i & 1) return {}; if(deg - i / 2 <= 0) break; auto ret = (*this >> i).sqrt(deg - i / 2); if(ret.empty()) return {}; ret = ret << (i / 2); if(ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return P(deg, 0); } P ret; if(get_sqrt() == nullptr) { assert((*this)[0] == T(1)); ret = {T(1)}; } else { auto sqr = get_sqrt()((*this)[0]); if(sqr * sqr != (*this)[0]) return {}; ret = {T(sqr)}; } T inv2 = T(1) / T(2); for(int i = 1; i < deg; i <<= 1) { ret = (ret + pre(i << 1) * ret.inv(i << 1)) * inv2; } return ret.pre(deg); } // F(0) must be 0 P exp(int deg = -1) const { assert((*this)[0] == T(0)); const int n = (int) this->size(); if(deg == -1) deg = n; if(get_fft() != nullptr) { P ret(*this); ret.resize(deg, T(0)); return ret.exp_rec(); } P ret({T(1)}); for(int i = 1; i < deg; i <<= 1) { ret = (ret * (pre(i << 1) + T(1) - ret.log(i << 1))).pre(i << 1); } return ret.pre(deg); } P online_convolution_exp(const P &conv_coeff) const { const int n = (int) conv_coeff.size(); assert((n & (n - 1)) == 0); vector< P > conv_ntt_coeff; auto& fft = get_fft(); auto& ifft = get_ifft(); for(int i = n; i >= 1; i >>= 1) { P g(conv_coeff.pre(i)); fft(g); conv_ntt_coeff.emplace_back(g); } P conv_arg(n), conv_ret(n); auto rec = [&](auto rec, int l, int r, int d) -> void { if(r - l <= 16) { for(int i = l; i < r; i++) { T sum = 0; for(int j = l; j < i; j++) sum += conv_arg[j] * conv_coeff[i - j]; conv_ret[i] += sum; conv_arg[i] = i == 0 ? T(1) : conv_ret[i] / i; } } else { int m = (l + r) / 2; rec(rec, l, m, d + 1); P pre(r - l); for(int i = 0; i < m - l; i++) pre[i] = conv_arg[l + i]; fft(pre); for(int i = 0; i < r - l; i++) pre[i] *= conv_ntt_coeff[d][i]; ifft(pre); for(int i = 0; i < r - m; i++) conv_ret[m + i] += pre[m + i - l]; rec(rec, m, r, d + 1); } }; rec(rec, 0, n, 0); return conv_arg; } P exp_rec() const { assert((*this)[0] == T(0)); const int n = (int) this->size(); int m = 1; while(m < n) m *= 2; P conv_coeff(m); for(int i = 1; i < n; i++) conv_coeff[i] = (*this)[i] * i; return online_convolution_exp(conv_coeff).pre(n); } P inv_fast() const { assert(((*this)[0]) != T(0)); const int n = (int) this->size(); P res{T(1) / (*this)[0]}; for(int d = 1; d < n; d <<= 1) { P f(2 * d), g(2 * d); for(int j = 0; j < min(n, 2 * d); j++) f[j] = (*this)[j]; for(int j = 0; j < d; j++) g[j] = res[j]; get_fft()(f); get_fft()(g); for(int j = 0; j < 2 * d; j++) f[j] *= g[j]; get_ifft()(f); for(int j = 0; j < d; j++) { f[j] = 0; f[j + d] = -f[j + d]; } get_fft()(f); for(int j = 0; j < 2 * d; j++) f[j] *= g[j]; get_ifft()(f); for(int j = 0; j < d; j++) f[j] = res[j]; res = f; } return res.pre(n); } P pow(int64_t k, int deg = -1) const { const int n = (int) this->size(); if(deg == -1) deg = n; for(int i = 0; i < n; i++) { if((*this)[i] != T(0)) { T rev = T(1) / (*this)[i]; P ret = (((*this * rev) >> i).log(deg) * k).exp(deg) * ((*this)[i].pow(k)); if(i * k > deg) return P(deg, T(0)); ret = (ret << (i * k)).pre(deg); if(ret.size() < deg) ret.resize(deg, T(0)); return ret; } } return *this; } T eval(T x) const { T r = 0, w = 1; for(auto &v : *this) { r += w * v; w *= x; } return r; } P pow_mod(int64_t n, P mod) const { P modinv = mod.rev().inv(); auto get_div = [&](P base) { if(base.size() < mod.size()) { base.clear(); return base; } int n = base.size() - mod.size() + 1; return (base.rev().pre(n) * modinv.pre(n)).pre(n).rev(n); }; P x(*this), ret{1}; while(n > 0) { if(n & 1) { ret *= x; ret -= get_div(ret) * mod; } x *= x; x -= get_div(x) * mod; n >>= 1; } return ret; } void mul(vector<pair<int, T>> g, bool extend = false){ if(extend)this->resize(this->size() + g.back().first); int n = this->size(); int d = g[0].first; T c = g[0].second; if(d == 0)g.erase(g.begin()); else c = 0; for(int i = n - 1; i >= 0; i--){ (*this)[i] *= c; for(auto z : g){ if(z.first > i)continue; (*this)[i] += (*this)[i-z.first] * z.second; } } } void div(vector<pair<int, T>>g){//定数項は非ゼロ int n = this->size(); int d = g[0].first; T c = g[0].second; c = T(1) / c; g.erase(g.begin()); for(int i = 0; i < n; i++){ for(auto z : g){ if(z.first > i)continue; (*this)[i] -= (*this)[i-z.first] * z.second; } (*this)[i] *= c; } } }; /* NumberTheoreticTransformFriendlyModInt<modint> ntt; auto mult=[&](const FPS &x,const FPS &y){ auto ret = ntt.multiply(x,y); return FPS(ret.begin(),ret.end()); }; FPS::set_mult(mult); FPS::set_fft([&](FPS &a){return ntt.ntt(a);},[&](FPS &b){return ntt.intt(b);}); */ /* using FPS=FormalPowerSeries<modint>; ArbitraryModConvolution<modint> ntt; auto mult=[&](const FPS &x,const FPS &y){ auto ret = ntt.multiply(x,y); return FPS(ret.begin(),ret.end()); }; FPS::set_mult(mult); */ template< int mod > struct ModInt { int x; ModInt() : x(0) {} ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {} ModInt &operator+=(const ModInt &p) { if((x += p.x) >= mod) x -= mod; return *this; } ModInt &operator-=(const ModInt &p) { if((x += mod - p.x) >= mod) x -= mod; return *this; } ModInt &operator*=(const ModInt &p) { x = (int) (1LL * x * p.x % mod); return *this; } ModInt &operator/=(const ModInt &p) { *this *= p.inverse(); return *this; } ModInt operator-() const { return ModInt(-x); } friend ModInt operator+(const ModInt& lhs, const ModInt& rhs) { return ModInt(lhs) += rhs; } friend ModInt operator-(const ModInt& lhs, const ModInt& rhs) { return ModInt(lhs) -= rhs; } friend ModInt operator*(const ModInt& lhs, const ModInt& rhs) { return ModInt(lhs) *= rhs; } friend ModInt operator/(const ModInt& lhs, const ModInt& rhs) { return ModInt(lhs) /= rhs; } bool operator==(const ModInt &p) const { return x == p.x; } bool operator!=(const ModInt &p) const { return x != p.x; } ModInt inverse() const { int a = x, b = mod, u = 1, v = 0, t; while(b > 0) { t = a / b; swap(a -= t * b, b); swap(u -= t * v, v); } return ModInt(u); } ModInt pow(int64_t n) const { ModInt ret(1), mul(x); while(n > 0) { if(n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } friend ostream &operator<<(ostream &os, const ModInt &p) { return os << p.x; } friend istream &operator>>(istream &is, ModInt &a) { int64_t t; is >> t; a = ModInt< mod >(t); return (is); } static int get_mod() { return mod; } }; using modint = ModInt< MOD1 >;modint pow(ll n, ll x){return modint(n).pow(x);}modint pow(modint n, ll x){return n.pow(x);} //using modint=ld; template< class T > FormalPowerSeries< T > berlekamp_massey(const FormalPowerSeries< T > &s) { const int N = (int) s.size(); FormalPowerSeries< T > b = {T(-1)}, c = {T(-1)}; T y = T(1); for(int ed = 1; ed <= N; ed++) { int l = int(c.size()), m = int(b.size()); T x = 0; for(int i = 0; i < l; i++) x += c[i] * s[ed - l + i]; b.emplace_back(0); m++; if(x == T(0)) continue; T freq = x / y; if(l < m) { auto tmp = c; c.insert(begin(c), m - l, T(0)); for(int i = 0; i < m; i++) c[m - 1 - i] -= freq * b[m - 1 - i]; b = tmp; y = x; } else { for(int i = 0; i < m; i++) c[l - 1 - i] -= freq * b[m - 1 - i]; } } return c; } template< class T> struct Kitamasa { ll n; const T zero = 0;//addの単位元 const T iden = 1;//mulの単位元 using arr = vector<T>; arr rec_f; const T add(T x, T y){ return x + y; } const T mul(T x, T y){ return x * y; } arr zeros(){ arr ret(n); for(ll i=0;i<n;i++)ret[i]=zero; return ret; } Kitamasa(vector<T> v):n(v.size()){ //an=sum(v0*a_(n-k)+v_1*a_(n-k+1)+... rec_f = zeros(); for(ll i=0;i<n;i++)rec_f[i]=v[i]; } T calc(ll k, vector<T> a){//k項目を求める, a0...ak-1 vector<ll>bit; while(k){ if(k&1)bit.push_back(1); else bit.push_back(0); k>>=1; } reverse(bit.begin(),bit.end()); arr now=zeros(); now[0]=iden; for(ll i=0;i<bit.size();i++){ now=twice(now); if(bit[i]==1)now=increment(now); } T ret=zero; for(ll i=0;i<n;i++)ret=add(ret,mul(now[i],a[i])); return ret; } arr increment(arr &v){ arr ret=zeros(); for(ll i=1;i<n;i++)ret[i]=add(v[i-1],mul(v[n-1],rec_f[i])); ret[0]=mul(v[n-1],rec_f[0]); return ret; } arr twice(arr &v){ arr ret=zeros(); arr tmp=v; for(ll i=0;i<n;i++){ for(ll j=0;j<n;j++){ ret[j]=add(ret[j],mul(v[i],tmp[j])); } tmp=increment(tmp); } return ret; } }; int main(){ cin.tie(nullptr); ios_base::sync_with_stdio(false); ll res=0,buf=0; bool judge = true; ll n;cin>>n; ll a,b,k;cin>>a>>b>>k; using FPS=FormalPowerSeries<modint>; FPS f(100); f[0]=a,f[1]=b; rep(i,0,100){ if(i>1)f[i]=(f[i-1]*f[i-1]+k)/f[i-2]; } //ebug(f); auto c=berlekamp_massey(f); c.resize(c.size()-1); //c.erase(c.begin()); Kitamasa kit(c); f.resize(c.size()); cout<<kit.calc(n-1,f)<<endl;; return 0; }