#include template class Trie { struct Node { std::array nxt; Node() { std::ranges::fill(nxt, -1); } }; protected: std::vector nodes; public: Trie() : nodes(1, Node()) {} int &nxt(size_t v, char c) { return nodes[v].nxt[c - MARGIN]; } size_t add(const std::string &s) { size_t now = 0; for (char c : s) { if (nxt(now, c) < 0) { nxt(now, c) = nodes.size(); nodes.push_back(Node()); } now = nxt(now, c); } return now; } std::vector add(const std::vector &v) { std::vector ret; ret.reserve(v.size()); for (const std::string &s : v) ret.push_back(add(s)); return ret; } }; template class AhoCorasick : Trie { using super = Trie; using super::nodes; std::vector> vertex_counts; public: using super::nxt; using super::Trie; std::vector add(const std::vector &v) { auto ret = super::add(v); size_t n = nodes.size(); vertex_counts.resize(n); std::vector exist(n, false); for (size_t v : ret) exist[v] = true; std::vector suffix(n); std::queue que; que.push(0); while (que.size()) { size_t v = que.front(); que.pop(); if (v) { if (exist[v]) vertex_counts[v][v]++; for (const auto &[key, value] : vertex_counts[suffix[v]]) vertex_counts[v][key] += value; } for (size_t i = 0; i < SIGMA; i++) { int &to = nodes[v].nxt[i]; if (~to) { suffix[to] = v ? nodes[suffix[v]].nxt[i] : 0; que.push(to); } else to = v ? nodes[suffix[v]].nxt[i] : 0; } } return ret; } const std::map &count(size_t v) const { return vertex_counts[v]; } std::map path(const std::string &s) const { std::map ret; size_t v = 0; for (const char &c : s) { v = nxt(v, c); for (const auto &[key, value] : vertex_counts) ret[key] += value; } return ret; } }; #include using mint = atcoder::modint1000000007; int main() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); int n; std::cin >> n; uint64_t l, r; std::cin >> l >> r; std::vector fib{1, 2}; while (fib.back() < r) fib.push_back(fib[fib.size() - 2] + fib[fib.size() - 1]); std::vector v; for (const auto &x : fib) { if (std::clamp(x, l, r) != x) continue; v.push_back(std::to_string(x)); } AhoCorasick<10, '0'> T; T.add(v); std::map dp{{0, 1}}; while (n--) { std::map nxt; for (const auto &[v, val] : dp) { for (char c = '0'; c <= '9'; c++) { size_t to = T.nxt(v, c); if (T.count(to).size()) continue; nxt[to] += val; } } dp = nxt; } mint ans = -1; for (const auto &[key, val] : dp) ans += val; std::cout << ans.val() << '\n'; }