This documentation is automatically generated by online-judge-tools/verification-helper
View the Project on GitHub ngthanhtrung23/ACM_Notebook_new
#include "../Misc/compress.h" // Returns number of distinct, non-empty subsequences {{{ // T = type of input elements // OutT = type of output (e.g. ModInt) template<typename T, typename OutT> OutT cnt_distinct_subsequences(std::vector<T> a) { auto compressor = CompressorBuilder<T>{a}.build(); compressor.compress_inplace(a); std::vector<OutT> f(a.size() + 1); std::vector<int> last(a.size() + 1, -1); f[0] = 1; for (size_t i = 0; i < a.size(); ++i) { f[i+1] = f[i] * 2; if (last[a[i]] >= 0) f[i+1] -= f[last[a[i]]]; last[a[i]] = i; } return f.back() - 1; } // }}}
#line 1 "Misc/compress.h" // Compressor {{{ /* Example usage: auto compressor = CompressorBuilder<T>{vs}.build(); int x = compessor.must_eq(vs[0]); compressor.compress_inplace(vs); */ // Based on https://suisen-cp.github.io/cp-library-cpp/library/util/coordinate_compressor.hpp template<typename T> struct CompressorBuilder { // Do not use directly. Use builder.build() struct Compressor { // Number of unique keys int size() const { return xs.size(); } void compress_inplace(std::vector<T>& vals) { for (int& val : vals) { val = must_eq(val); } } [[nodiscard]] std::vector<T> compress(const std::vector<T>& vals) { std::vector<T> res(vals.size()); for (int i = 0; i < static_cast<int> (res.size()); ++i) { res[i] = must_eq(vals[i]); } return res; } bool has_key(const T& key) const { return std::binary_search(xs.begin(), xs.end(), key); } #define LB(key) std::lower_bound(xs.begin(), xs.end(), key) #define UB(key) std::upper_bound(xs.begin(), xs.end(), key) std::optional<int> eq(const T& key) { auto it = LB(key); return it == xs.end() ? std::nullopt : std::optional<int>{it - xs.begin()}; } std::optional<int> geq(const T& key) { auto it = LB(key); return it == xs.end() ? std::nullopt : std::optional<int>{it - xs.begin()}; } std::optional<int> gt(const T& key) { auto it = UB(key); return it == xs.end() ? std::nullopt : std::optional<int>{it - xs.begin()}; } std::optional<int> leq(const T& key) { auto it = UB(key); return it == xs.begin() ? std::nullopt : std::optional<int>{it - xs.begin() - 1}; } std::optional<int> lt(const T& key) { auto it = LB(key); return it == xs.begin() ? std::nullopt : std::optional<int>{it - xs.begin() - 1}; } // throw exception if no such key is found int must_eq(const T& key) { auto it = LB(key); assert(it != xs.end()); return it - xs.begin(); } // throw exception if no such key is found int must_geq(const T& key) { auto it = LB(key); assert(it != xs.end()); return it - xs.begin(); } // throw exception if no such key is found int must_gt(const T& key) { auto it = UB(key); assert(it != xs.end()); return it - xs.begin(); } // throw exception if no such key is found int must_leq(const T& key) { auto it = UB(key); assert(it != xs.begin()); return it - xs.begin() - 1; } // throw exception if no such key is found int must_lt(const T& key) { auto it = LB(key); assert(it != xs.begin()); return it - xs.begin() - 1; } #undef LB #undef UB std::vector<T> xs; }; auto build() { std::sort(xs.begin(), xs.end()); xs.erase(std::unique(xs.begin(), xs.end()), xs.end()); return Compressor{xs}; } void add(const T& key) { xs.push_back(key); } void add(T&& key) { xs.push_back(std::move(key)); } std::vector<T> xs; }; // }}} #line 2 "DP/cnt_distinct_subseq.h" // Returns number of distinct, non-empty subsequences {{{ // T = type of input elements // OutT = type of output (e.g. ModInt) template<typename T, typename OutT> OutT cnt_distinct_subsequences(std::vector<T> a) { auto compressor = CompressorBuilder<T>{a}.build(); compressor.compress_inplace(a); std::vector<OutT> f(a.size() + 1); std::vector<int> last(a.size() + 1, -1); f[0] = 1; for (size_t i = 0; i < a.size(); ++i) { f[i+1] = f[i] * 2; if (last[a[i]] >= 0) f[i+1] -= f[last[a[i]]]; last[a[i]] = i; } return f.back() - 1; } // }}}