#1150069 (C++23) No.3457 Fibo-shrink

• 問題: No.3457 Fibo-shrink
• ユーザー: AD010
• 提出日時: 2026-02-28 14:02:01
• 言語: C++23 (gcc 15.2.0 + boost 1.89.0)
• 結果: AC
• 実行時間: 418 ms / 2,000 ms
• コード長: 3,694 bytes
• コンパイル時間: 3,554 ms
• コンパイル使用メモリ: 340,044 KB
• 実行使用メモリ: 7,844 KB
• 最終ジャッジ日時: 2026-02-28 14:02:08
• 合計ジャッジ時間: 6,219 ms
• ジャッジサーバーID （参考情報）: judge7 / judge1

ファイルパターン	結果
sample	AC * 2
other	AC * 12

ソースコード

#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define ull unsigned long long
#define ld  long double

using LL = long long; using ULL = unsigned long long;
using VI = vector<int>; using VVI = vector<VI>; using VVVI = vector<VVI>;
using VL = vector<LL>; using VVL = vector<VL>; using VVVL = vector<VVL>;
using VB = vector<bool>; using VVB = vector<VB>; using VVVB = vector<VVB>;
using VD = vector<double>; using VVD = vector<VD>; using VVVD = vector<VVD>;
using VC = vector<char>; using VS = vector<string>; using VVC = vector<VC>;
using PII = pair<int,int>; using PLL = pair<LL,LL>; using PDD = pair<double,double>; using PIL = pair<int,LL>;
using MII = map<int,int>; using MLL = map<LL,LL>;
using SI = set<int>; using SL = set<LL>;
using MSI = multiset<int>; using MSL = multiset<LL>;
template<class T> using MAXPQ = priority_queue<T>;
template<class T> using MINPQ = priority_queue< T, vector<T>, greater<T> >;

const ll MOD = 1000000007;
const ll MOD2 = 998244353;
const ll INF = 1LL << 60;
#define PI  3.14159265358979323846

#define FOR(i, a, b) for(int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)
#define EACH(e, v) for(auto &e : v)
#define RITR(it, v) for(auto it = (v).rbegin(); it != (v).rend(); ++it)
#define ALL(v) v.begin(),v.end()

vector<ll> x8={1,1,1,0,0,-1,-1,-1},y8={1,0,-1,1,-1,1,0,-1};
int dx4[4]={1,-1,0,0}, dy4[4]={0,0,1,-1};

/*
memo
-uf,RMQ(segtree),BIT,BIT2,SegTree,SegTreeLazy
-isprime,Eratosthenes,gcdlcm,factorize,divisors,modpow,moddiv
nCr(+modnCr,inverse,extend_euclid.powmod),tobaseB,tobase10
-dijkstra,Floyd,bellmanford,sccd,topological,treediamiter
-compress1,compress2,rotate90

-co,ci,fo1,fo2,fo3,fo4
-bitsearch,binaryserach
-bfs
-SegTreedec,SegTreeLazydec
*/

template <int mod>
class mint {
public:
    long long x;
    constexpr mint(long long x=0) : x((x%mod+mod)%mod) {}
    constexpr mint operator-() const { 
      return mint(-x);
    }
    constexpr mint& operator+=(const mint& a) {
        if ((x += a.x) >= mod) x -= mod;
        return *this;
    }
    constexpr mint& operator-=(const mint& a) {
        if ((x += mod-a.x) >= mod) x -= mod;
        return *this;
    }
    constexpr mint& operator*=(const mint& a) {
        (x *= a.x) %= mod;
        return *this;
    }
    constexpr mint operator+(const mint& a) const {
        mint res(*this);
        return res+=a;
    }
    constexpr mint operator-(const mint& a) const {
        mint res(*this);
        return res-=a;
    }
    constexpr mint operator*(const mint& a) const {
        mint res(*this);
        return res*=a;
    }
    constexpr mint pow(long long t) const {
        if (!t) return 1;
        mint a = pow(t>>1);
        a *= a;
        if (t&1) a *= *this;
        return a;
    }

    // for prime mod
    constexpr mint inv() const {
        return pow(mod-2);
    }
    constexpr mint& operator/=(const mint& a) {
        return (*this) *= a.inv();
    }
    constexpr mint operator/(const mint& a) const {
        mint res(*this);
        return res/=a;
    }
};
using mint1 = mint<10007>;
using mint2 = mint<998244353>;
using VM = vector<mint1>;

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    ll K,S,N; cin >> K >> S >> N;
    VM F(K+1);
    F[0]=1;
    F[1]=1;
    for(ll i = 2; i <= K; i++) F[i] = (F[i-1]+F[i-2]);

    VM V(N+1);
    V[1] = S;
    for(ll i = 2; i <= N; i++){
        mint1 res = 0;
        for(ll j = 1; j <= K+1; j++){
            if(i-j >= 1){
                mint1 v = V[i-j];
                mint1 inv = F[j-1];
                inv = mint1(1)/inv;
                v *= inv;
                res += v;
            }
        }
        V[i] = res;
    }

    cout << V[N].x << '\n';
    
    
}