pennant.cpp

#include <stack>
#include "node.h"
#include "pennant.h"

Pennant::Pennant(Node* root) {
	this->root = root;
}

Pennant::~Pennant() {
	if (this->root != NULL) {
		std::stack<Node *> nodes;
	
		nodes.push(this->root);
		while (nodes.size() > 0) {
			Node *current = nodes.top();
			nodes.pop();

			if (current->left != NULL) {
				nodes.push(current->left);
			}

			if (current->right != NULL) {
				nodes.push(current->right);
			}

			delete current;
		}
	}
}

void Pennant::p_merge(Pennant *&y) {
	if (y == NULL) return;

	y->root->right = this->root->left;
	this->root->left = y->root;
	y->root = NULL;
	delete y;
	y = NULL;
}

Pennant* Pennant::p_split() {
	if (this->root->left == NULL) {
		return NULL;
	}
	
	Pennant *y = new Pennant(this->root->left);
	this->root->left = y->root->right;
	y->root->right = NULL;
	return y;
}

void Pennant::FA(Pennant *&x, Pennant *&y, Pennant *&carry) {
	if (x == NULL && y == NULL && carry == NULL) {
		return;
	}
	if (x != NULL && y == NULL && carry == NULL) {
		return;
	}
	if (x == NULL && y != NULL && carry == NULL) {
		x = y;
		y = NULL;
		return;
	}
	if (x == NULL && y == NULL && carry != NULL) {
		x = carry;
		carry = NULL;
		return;
	}
	if (x != NULL && y != NULL && carry == NULL) {
		x->p_merge(y);
		carry = x;
		x = NULL;
		return;
	}
	if (x != NULL && y == NULL && carry != NULL) {
		x->p_merge(carry);
		carry = x;
		x = NULL;
		return;
	}
	if (x == NULL && y != NULL && carry != NULL) {
		y->p_merge(carry);
		carry = y;
		y = NULL;
		return;
	}
	if (x != NULL && y != NULL && carry != NULL) {
		carry->p_merge(y);
		return;
	}
}