#ifndef JIKKA_SLOPE_TRICK #define JIKKA_SLOPE_TRICK /** * @brief Slope-Trick * @author ei1333 (original author) * @author Kimiyuki Onaka (maintainer) * @copyright The Unlicense * @see https://maspypy.com/slope-trick-1-%E8%A7%A3%E8%AA%AC%E7%B7%A8 */ #include #include #include #include #include namespace jikka { template struct slope_trick { const T INF = std::numeric_limits::max() / 3; T min_f; std::priority_queue, std::less<>> L; std::priority_queue, std::greater<>> R; T add_l, add_r; private: void push_R(const T &a) { R.push(a - add_r); } T top_R() const { if (R.empty()) { return INF; } else { return R.top() + add_r; } } T pop_R() { T val = top_R(); if (not R.empty()) { R.pop(); } return val; } void push_L(const T &a) { L.push(a - add_l); } T top_L() const { if (L.empty()) { return -INF; } else { return L.top() + add_l; } } T pop_L() { T val = top_L(); if (not L.empty()) { L.pop(); } return val; } size_t size() { return L.size() + R.size(); } public: slope_trick() : min_f(0), add_l(0), add_r(0) {} struct query_t { T lx, rx, min_f; }; // return min f(x) query_t query() const { return (query_t){top_L(), top_R(), min_f}; } // f(x) += a void add_all(const T &a) { min_f += a; } // add \_ // f(x) += max(a - x, 0) void add_a_minus_x(const T &a) { min_f += std::max(T(0), a - top_R()); push_R(a); push_L(pop_R()); } // add _/ // f(x) += max(x - a, 0) void add_x_minus_a(const T &a) { min_f += std::max(T(0), top_L() - a); push_L(a); push_R(pop_L()); } // add \/ // f(x) += abs(x - a) void add_abs(const T &a) { add_a_minus_x(a); add_x_minus_a(a); } // \/ -> \_ // f_{new} (x) = min f(y) (y <= x) void clear_right() { while (not R.empty()) { R.pop(); } } // \/ -> _/ // f_{new} (x) = min f(y) (y >= x) void clear_left() { while (not L.empty()) { L.pop(); } } // \/ -> \_/ // f_{new} (x) = min f(y) (x-b <= y <= x-a) void shift(const T &a, const T &b) { assert(a <= b); add_l += a; add_r += b; } // \/. -> .\/ // f_{new} (x) = f(x - a) void shift(const T &a) { shift(a, a); } // L, R を破壊する T get(const T &x) { T ret = min_f; while (not L.empty()) { ret += std::max(T(0), pop_L() - x); } while (not R.empty()) { ret += std::max(T(0), x - pop_R()); } return ret; } void merge(slope_trick &st) { if (st.size() > size()) { std::swap(st.L, L); std::swap(st.R, R); std::swap(st.add_l, add_l); std::swap(st.add_r, add_r); std::swap(st.min_f, min_f); } while (not st.R.empty()) { add_x_minus_a(st.pop_R()); } while (not st.L.empty()) { add_a_minus_x(st.pop_L()); } min_f += st.min_f; } }; } // namespace jikka #endif // JIKKA_SLOPE_TRICK