school/cs235/lab03/Student_Code/linkedlist.cpp
2016-04-06 20:46:10 -07:00

159 lines
3.8 KiB
C++

#include "linkedlist.h"
linkedlist::linkedlist(): head(NULL) {}
linkedlist::~linkedlist(){clear();}
bool linkedlist::is_it_zero(int value) {
if(value < 0)
return false;
else
return true;
}
bool linkedlist::has_a(int value) {
// cout << "has_a(" << value << ")" << endl;
node* node_ptr = head;
if(head == NULL)
return false;
while(node_ptr != NULL) {
if(node_ptr->value == value)
return true;
node_ptr = node_ptr->next;
}
return false;
}
void linkedlist::insertHead(int value) {
// cout << "inserthead(" << value << ")" << endl;
// cout << *this << endl;
if(!is_it_zero(value))
return;
if(has_a(value))
return;
head = new node(value, head);
// cout << *this << endl << endl;
}
void linkedlist::insertTail(int value) {
// cout << "insertTail(" << value << ")" << endl;
// cout << *this << endl;
if(!is_it_zero(value))
return;
if(has_a(value))
return;
if(head == NULL) {
insertHead(value);
return;
}
node* node_ptr = head;
while(node_ptr != NULL) {
if(node_ptr->next == NULL) {
node_ptr->next = new node(value, NULL);
break;
}
node_ptr = node_ptr->next;
}
// cout << *this << endl << endl;
}
void linkedlist::insertAfter(int value, int insertionNode) {
// cout << "insertAfter(" << value << ", insertionNode" << insertionNode << ")" << endl;
// cout << *this << endl;
if(value < 0 || insertionNode < 0) {
//cout << "first check" << endl;
return;
}
if(has_a(value) || !has_a(insertionNode)) {
//cout << "failing" << endl;
return;
}
node* node_ptr = head;
while(node_ptr != NULL) {
if(node_ptr->value == insertionNode) {
node* temp = new node(value, NULL);
temp->next = node_ptr->next;
node_ptr->next = temp;
}
node_ptr = node_ptr->next;
}
// cout << *this << endl << endl;
}
void linkedlist::remove(int value) {
// cout << "remove(" << value << ")" << endl;
// cout << *this << endl;
if(!is_it_zero(value))
return;
if(!has_a(value))
return;
node* node_ptr = head;
if(node_ptr->value == value) {
//cout << "first" << endl;
node* ptr = head;
head = head->next;
delete ptr;
return;
}
while(node_ptr != NULL) {
if(node_ptr->next == NULL)
return;
if(node_ptr->next->value == value) {
node* ptr = node_ptr->next;
node_ptr->next = node_ptr->next->next;
delete ptr;
}
node_ptr = node_ptr->next;
}
// cout << *this << endl << endl;
}
void linkedlist::clear() {
// cout << "clear()" << endl;
node* node_ptr = head;
while(head) {
node_ptr = head;
head = head->next;
delete node_ptr;
}
}
int linkedlist::at(int index) {
// cout << *this << endl;
// cout << "at(" << index << ")" << endl;
if(index < 0) {
//cout << "is it zero" << endl;
return -1;
}
if(size() <= index) {
// cout << "this is the index=" << index << " size(" << size() << ")"<<endl;
return -1;
}
node* node_ptr = head;
for(int i = 0; i < index; i++){
node_ptr = node_ptr->next;
}
if(head == NULL)
return -1;
return node_ptr->value;
}
int linkedlist::size() {
int size_of_list = 0;
node* node_ptr = head;
while(node_ptr != NULL) {
size_of_list++;
node_ptr = node_ptr->next;
}
// cout << "size(" << size_of_list << ")" << endl;
return size_of_list;
}
ostream & operator<<(ostream & os, linkedlist & f) {
node* node_ptr = f.head;
while(node_ptr != NULL) {
os << node_ptr->value << ",";
node_ptr = node_ptr->next;
}
return os;
}