110 lines
1.9 KiB
C++
110 lines
1.9 KiB
C++
/* btree.cpp
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* Date: 2021-11-22
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* Author: Aryadev Chavali
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*/
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#include <iostream>
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enum Order
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{
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LT,
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GT,
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EQ
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};
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template <typename T>
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struct BinaryTree
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{
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T value;
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BinaryTree<T> *left, *right;
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enum Order (*compare)(T, T);
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BinaryTree(T val, BinaryTree<T> *l, BinaryTree<T> *r, enum Order (*cmp)(T, T))
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{
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value = val;
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left = l;
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right = r;
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compare = cmp;
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}
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~BinaryTree()
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{
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delete left;
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delete right;
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}
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};
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template <typename T>
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BinaryTree<T> *insert(BinaryTree<T> *tree, T value)
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{
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BinaryTree<T> **node = &tree;
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switch (tree->compare(value, tree->value))
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{
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case LT:
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node = &tree->left;
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break;
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case EQ:
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case GT:
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node = &tree->right;
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break;
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}
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*node = *node ? insert(*node, value)
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: new BinaryTree<T>(value, nullptr, nullptr, tree->compare);
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return tree;
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}
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template <typename T>
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void rightRotate(BinaryTree<T> **tree)
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{
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auto left = *tree->left;
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*tree->left = left->right;
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left->right = *tree;
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*tree = left;
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}
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template <typename T>
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void leftRotate(BinaryTree<T> **tree)
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{
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auto right = (*tree)->right;
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(*tree)->right = right->left;
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right->left = *tree;
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*tree = right;
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}
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template <typename T>
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std::ostream &operator<<(std::ostream &ostream, const BinaryTree<T> *btree)
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{
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if (!btree)
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return ostream;
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ostream << btree->value << "(";
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if (btree->left)
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ostream << btree->left;
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if (btree->left && btree->right)
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ostream << ", ";
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if (btree->right)
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ostream << btree->right;
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ostream << ")";
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return ostream;
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}
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int main(void)
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{
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auto cmp = [](int x, int y)
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{
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if (x < y)
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return LT;
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else if (x > y)
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return GT;
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else
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return EQ;
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};
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auto tree = new BinaryTree<int>(5, NULL, NULL, cmp);
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for (int i = 0; i <= 5; ++i)
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tree = insert(tree, i * 2);
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leftRotate(&tree);
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std::cout << tree << std::endl;
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delete tree;
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return 0;
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}
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