Last active
June 28, 2019 10:03
-
-
Save finalchild/b3d970e83a02d54322eea00e0d8ecb29 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| template<typename T, const T& Combine(const T&, const T&)> | |
| class segment_tree { | |
| darray<T> v; | |
| T default_value; | |
| T combine_considering_default(const T& left_value, const T& right_value) const { | |
| if (left_value == default_value) { | |
| return right_value; | |
| } else if (right_value == default_value) { | |
| return left_value; | |
| } else { | |
| return Combine(left_value, right_value); | |
| } | |
| } | |
| public: | |
| explicit segment_tree(usize size) : default_value(T()) { | |
| v.reserve(size << 1u); | |
| for (usize i = 0u; i < size; i++) v.push_back(default_value); | |
| for (usize i = 0u; i < size; i++) v.push_back(default_value); | |
| } | |
| segment_tree(usize size, T default_value) : default_value(default_value) { | |
| v.reserve(size << 1u); | |
| for (usize i = 0u; i < size; i++) v.push_back(default_value); | |
| for (usize i = 0u; i < size; i++) v.push_back(default_value); | |
| } | |
| explicit segment_tree(const darray<T>& values_src) : default_value(T()) { | |
| v.reserve(values_src.size() << 1u); | |
| for (usize i = 0u; i < values_src.size(); i++) v.push_back(default_value); | |
| for (usize i = 0u; i < values_src.size(); i++) v.push_back(values_src[i]); | |
| update_all(); | |
| } | |
| segment_tree(const darray<T>& values_src, T default_value) : default_value(default_value) { | |
| v.reserve(values_src.size() << 1u); | |
| for (usize i = 0u; i < values_src.size(); i++) v.push_back(default_value); | |
| for (usize i = 0u; i < values_src.size(); i++) v.push_back(values_src[i]); | |
| update_all(); | |
| } | |
| segment_tree(const segment_tree& src) : v(src.v), default_value(src.default_value) {} | |
| segment_tree(segment_tree&& src) noexcept : v(move(src.v)), default_value(move(src.default_value)) {} | |
| segment_tree& operator=(const segment_tree& src) { self = segment_tree(src); return self; } | |
| segment_tree& operator=(segment_tree&& src) noexcept { v = move(src.v); default_value = move(src.default_value); return self; } | |
| void modify_without_update(usize i, const T& value) { | |
| v[(v.size() >> 1u) + i] = value; | |
| } | |
| void modify(usize i, const T& value) { | |
| modify_without_update(i, move(value)); | |
| for (usize v_index = ((v.size() >> 1u) + i >> 1u); v_index > 0u; v_index >>= 1u) { | |
| update(v_index); | |
| } | |
| } | |
| void update(usize v_index) { | |
| if (v_index == 0u || v_index >= (v.size() >> 1u)) return; | |
| v[v_index] = combine_considering_default(v[(v_index << 1u)], v[(v_index << 1u) | 1u]); | |
| } | |
| void update_all() { | |
| for (usize v_index = (v.size() >> 1u) - 1u; v_index > 0u; v_index--) update(v_index); | |
| } | |
| T query(usize begin, usize end) const { | |
| T result_left = default_value; | |
| T result_right = default_value; | |
| for (usize left = begin + (v.size() >> 1u), right = end + (v.size() >> 1u); left < right; left >>= 1u, right >>= 1u) { | |
| if (left & 1u) { | |
| result_left = combine_considering_default(result_left, v[left]); | |
| left++; | |
| } | |
| if (right & 1u) { | |
| result_right = combine_considering_default(v[right - 1u], result_right); | |
| right--; | |
| } | |
| } | |
| return combine_considering_default(result_left, result_right); | |
| } | |
| }; |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
파차귀여워~~