#include #include #include #pragma GCC optimize("O2,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") using namespace std; using namespace __gnu_pbds; // https://mirror.codeforces.com/blog/entry/124683 namespace hashing { using i64 = std::int64_t; using u64 = std::uint64_t; static const u64 FIXED_RANDOM = std::chrono::steady_clock::now().time_since_epoch().count(); #if USE_AES std::mt19937 rd(FIXED_RANDOM); const __m128i KEY1{(i64)rd(), (i64)rd()}; const __m128i KEY2{(i64)rd(), (i64)rd()}; #endif template struct custom_hash {}; template inline void hash_combine(u64 &seed, T const &v) { custom_hash hasher; seed ^= hasher(v) + 0x9e3779b97f4a7c15 + (seed << 12) + (seed >> 4); }; template struct custom_hash::value>::type> { u64 operator()(T _x) const { u64 x = _x; #if USE_AES __m128i m{i64(u64(x) * 0xbf58476d1ce4e5b9u64), (i64)FIXED_RANDOM}; __m128i y = _mm_aesenc_si128(m, KEY1); __m128i z = _mm_aesenc_si128(y, KEY2); return z[0]; #else x += 0x9e3779b97f4a7c15 + FIXED_RANDOM; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31); #endif } }; template struct custom_hash()))>> { u64 operator()(T const &a) const { u64 value = FIXED_RANDOM; for (auto &x : a) hash_combine(value, x); return value; } }; template struct custom_hash> { u64 operator()(const std::tuple &a) const { u64 value = FIXED_RANDOM; std::apply([&value](T const &...args) { (hash_combine(value, args), ...); }, a); return value; } }; template struct custom_hash> { u64 operator()(std::pair const &a) const { u64 value = FIXED_RANDOM; hash_combine(value, a.first); hash_combine(value, a.second); return value; } }; }; // namespace hashing #ifdef PB_DS_ASSOC_CNTNR_HPP template using hashmap = gp_hash_table< Key, Value, hashing::custom_hash, std::equal_to, direct_mask_range_hashing<>, linear_probe_fn<>, hash_standard_resize_policy, hash_load_check_resize_trigger<>, true>>; template using hashset = gp_hash_table< Key, null_type, hashing::custom_hash, std::equal_to, direct_mask_range_hashing<>, linear_probe_fn<>, hash_standard_resize_policy, hash_load_check_resize_trigger<>, true>>; #endif #ifdef PB_DS_TREE_POLICY_HPP template using multiset = tree, rb_tree_tag, tree_order_statistics_node_update>; template using rbtree = tree, rb_tree_tag, tree_order_statistics_node_update>; #endif #define ff first #define ss second #define eb emplace_back #define ll long long #define vec vector #define all(x) (x).begin(), (x).end() #define rall(x) (r).rbegin(), (x).rend() #define sz(x) static_cast((x).size()) #define FOR(a, b, c) for (int a = b; a < c; ++a) #ifdef LOCAL #define dbg(x) cout << __LINE__ << ": " << #x << "=<" << (x) << ">\n"; #else #define dbg(x) #endif template void print(string const &str, Args &&...args) { cout << vformat(str, make_format_args(forward(args)...)); } template void print(T const &t) { cout << t; } template void print(T const &t) { if constexpr (is_same_v || is_convertible_v) { cout << t << '\n'; } else { for (const auto &e : t) { cout << e << ' '; } cout << '\n'; } } template void println(string const &str, Args &&...args) { print(str, forward(args)...); cout << '\n'; } template void println(T const &t) { print("{}\n", t); } template void println(T const &t) { print(t); cout << '\n'; } void println() { cout << '\n'; } template T max() { return numeric_limits::max(); } template T min() { return numeric_limits::min(); } constexpr static int MOD = 1e9 + 7; void solve() { int n, k, d; cin >> n >> k >> d; hashmap, int> memo; auto dp = [&](auto &self, int n, int d) -> int { if (memo.find({n, d}) != memo.end()) return memo[{n, d}]; if (n == 0) return d == 0 ? 1 : 0; ll total = 0; FOR(i, 1, min(n + 1, k + 1)) { total = (total + self(self, n - i, i < d ? d : 0)) % MOD; } return memo[{n, d}] = total; }; print(dp(dp, n, d)); } int main() { cin.tie(nullptr)->sync_with_stdio(false); int t = 1; // cin >> t; while (t--) { solve(); } return 0; }