BLT/include/blt/std/binary_tree.h

329 lines
11 KiB
C++

/*
* Created by Brett on 09/01/23.
* Licensed under GNU General Public License V3.0
* See LICENSE file for license detail
*/
#ifndef BLT_BINARY_TREE_H
#define BLT_BINARY_TREE_H
#include <stdexcept>
#include <vector>
#include <blt/std/allocator.h>
#include <blt/std/types.h>
#include <iostream>
#include <memory>
// TODO: blt::queue
#include <queue>
#include <stack>
namespace blt
{
class binary_search_tree_error : public std::runtime_error
{
public:
explicit binary_search_tree_error(const std::string& string): runtime_error(string)
{}
};
template<typename T, typename ALLOC = blt::area_allocator<T>>
class AVL_node_tree
{
private:
ALLOC alloc;
struct node
{
T val;
node* left;
node* right;
ALLOC& alloc;
node(const T& t, ALLOC& alloc): val(t), alloc(alloc)
{}
node(T&& m, ALLOC alloc): val(m), alloc(alloc)
{}
node(const node& copy) = delete;
node(node&& move) = delete;
node& operator=(const node& copy) = delete;
node& operator=(node&& move) = delete;
~node()
{
left->~node();
alloc.deallocate(left);
right->~node();
alloc.deallocate(right);
}
};
inline node* newNode(T&& t)
{
return new(alloc.allocate(1)) node(t);
}
node* root = nullptr;
public:
AVL_node_tree() = default;
AVL_node_tree(const AVL_node_tree& copy) = delete;
AVL_node_tree(AVL_node_tree&& move) = delete;
AVL_node_tree& operator=(const AVL_node_tree& copy) = delete;
AVL_node_tree& operator=(AVL_node_tree&& move) = delete;
size_t height(node* start = nullptr)
{
if (start == nullptr)
start = root;
if (start == nullptr)
return 0;
std::queue<node*> nodes;
nodes.push(start);
size_t height = 0;
while (!nodes.empty())
{
height++;
size_t level_count = nodes.size();
while (level_count-- > 0)
{
if (nodes.front()->left != nullptr)
nodes.push(nodes.front()->left);
if (nodes.front()->right != nullptr)
nodes.push(nodes.front()->right);
nodes.pop();
}
}
return height;
}
void insert(const T& t)
{
if (root == nullptr)
{
root = newNode(t);
return;
}
node* search = root;
node* parent = nullptr;
while (true)
{
if (t < search->val)
{
if (search->left == nullptr)
{
search->left = newNode(t);
break;
}
search = search->left;
} else
{
if (search->right == nullptr)
{
search->right = newNode(t);
break;
}
search = search->right;
}
parent = search;
}
}
~AVL_node_tree()
{
root->~node();
alloc.deallocate(root);
}
};
template<typename K, typename V>
class range_tree_t
{
public:
struct node_t
{
K k;
V v;
blt::i64 children = 0;
node_t(K k, V v): k(std::move(k)), v(std::move(v))
{}
};
void insert(K k, V v)
{
auto insert_point = nodes.begin();
auto insert_parent = insert_point;
while (insert_point != nodes.end())
{
// no children
if (insert_point->children == 0)
{
++insert_point->children;
++insert_point;
break;
} else if (insert_point->children == 1)
{
// 1 child case
insert_parent = insert_point;
// find if child is min & move to it
++insert_point;
bool min = insert_point->k < insert_parent->k;
if (k < insert_parent->k)
{
// if the parent's child is a min value, then we can safely move towards it
if (min)
continue;
else
{
// otherwise we can break and this will insert the new node as the new min.
++insert_parent->children;
break;
}
} else
{
// parents child is min, so we move past it
if (min)
{
insert_point = skip_children(insert_point);
// can break as we insert here
++insert_parent->children;
break;
} else
{
// parents child is max, we can safely move towards it
continue;
}
}
} else
{
insert_parent = insert_point;
++insert_point;
if (k < insert_parent->k)
continue;
else
insert_point = skip_children(insert_point);
}
}
nodes.insert(insert_point, {std::move(k), std::move(v)});
}
void print(std::ostream& out, bool pretty_print)
{
std::stack<blt::size_t> left;
blt::size_t indent = 0;
for (auto& v : nodes)
{
if (v.children > 0)
{
create_indent(out, indent, pretty_print) << "(";
indent++;
left.emplace(v.children);
out << v.k << ": " << v.v << end_indent(pretty_print);
} else
create_indent(out, indent, pretty_print) << v.k << ": " << v.v << end_indent(pretty_print);
while (!left.empty())
{
auto top = left.top();
left.pop();
if (top == 0)
{
indent--;
create_indent(out, indent, pretty_print) << ")" << end_indent(pretty_print);
continue;
} else
{
if (!pretty_print)
out << " ";
left.push(top - 1);
break;
}
}
}
while (!left.empty())
{
auto top = left.top();
left.pop();
if (top == 0)
{
indent--;
create_indent(out, indent, pretty_print) << ")" << end_indent(pretty_print);
continue;
} else
{
out << "TREE MISMATCH";
break;
}
}
out << '\n';
}
std::optional<V> search(const K& k)
{
auto point = nodes.begin();
while (point != nodes.end())
{
if (k == point->k)
return point->v;
if (point->children == 0)
return {};
auto parent = point;
++point;
auto min = point->k < parent->k;
if (k >= parent->k)
{
if (min)
point = skip_children(point);
}
}
return {};
}
private:
auto skip_children(typename std::vector<node_t>::iterator begin)
{
blt::i64 children_left = 0;
do
{
if (children_left != 0)
children_left--;
if (begin->children > 0)
children_left += begin->children;
++begin;
} while (children_left > 0);
return begin;
}
std::ostream& create_indent(std::ostream& out, blt::size_t amount, bool pretty_print)
{
if (!pretty_print)
return out;
for (blt::size_t i = 0; i < amount; i++)
out << '\t';
return out;
}
std::string_view end_indent(bool pretty_print)
{
return pretty_print ? "\n" : "";
}
std::vector<node_t> nodes;
};
}
#endif //BLT_BINARY_TREE_H