adding cs235

2016-04-06 20:46:10 -07:00
parent 8e52ce1982
commit cf99ec6565
178 changed files with 13079 additions and 0 deletions
@@ -0,0 +1,169 @@
+#include "bst.h"
+
+bst::bst(): root(NULL){}
+
+bst::~bst() {
+    while(root) {
+        remove(root->data);
+    }
+}
+
+NodeInterface* bst::getRootNode() {
+    return root;
+}
+
+bool bst::add(int data) {
+    if(root == NULL) {
+        root = new node(data);
+        return true;
+    }
+    else {
+        node* current;
+        node* parent;
+        current = root;
+        while(current) {
+            parent = current;
+            if(data == current->data) {
+                return false;
+            }
+            if(data > current->data) {
+                current = current->right;
+            }
+            else {
+                current = current->left;
+            }
+        }
+        if(data < parent->data) {
+            parent->left = new node(data);
+            return true;
+        }
+        else {
+            parent->right = new node(data);
+            return true;;
+        }
+    }
+    return true;
+}
+
+bool bst::remove(int data) {
+    bool found = false;
+    if(root == NULL) {
+        return false;
+    }
+    node* current;
+    node* parent;
+    current = root;
+    while(current) {
+        if(current->data == data) {
+            found = true;
+            break;
+        }
+        else {
+            parent = current;
+            if(data > current->data) {
+                current = current->right;
+            }
+            else if(data < current->data) {
+                current = current->left;
+            }
+        }
+    }
+    if(!found) {
+        return false;
+    }
+    if(root->data == data) { 
+        if(root->right != NULL && root->left == NULL) {
+            node* temp;
+            temp = root;
+            root = root->right;
+            delete temp;
+            return true;
+        }
+        if(root->right == NULL && root->left != NULL) {
+            node* temp;
+            temp = root;
+            root = root->left;
+            delete temp;
+            return true;
+        }
+        if(root->right != NULL && root->left != NULL) {
+            node* temp;
+            temp = root;
+            root = root->left;
+            root->right = temp->right;
+            delete temp;
+            return true;
+        }
+        else {
+            delete root;
+            root = NULL;
+            return true;
+        }
+    }
+    if((current->left == NULL) && (current->right == NULL)) {
+        if(parent->left == current) {
+            parent->left = NULL;
+        }
+        else {
+            parent->right = NULL;
+        }
+        delete current;
+        return true;
+    }
+    if((current->left == NULL && current->right != NULL) || (current->left != NULL && current->right == NULL)) {
+        if(current->left == NULL && current->right != NULL) {
+            if(parent->left == current) {
+                parent->left = current->right;
+                delete current;
+            }
+            else {
+                parent->right = current->right;
+                delete current;
+            }
+        }
+        else {
+            if(parent->left == current) {
+                parent->left = current->left;
+                delete current;
+            }
+            else {
+                parent->right = current->left;
+                delete current;
+            }
+        }
+        return true;
+    }
+    if(current->left != NULL && current->right != NULL) {
+        node* greatest_right;
+        greatest_right = current->right;
+        if((greatest_right->left == NULL) && (greatest_right->right == NULL)) {
+            current = greatest_right;
+            delete greatest_right;
+            current->right = NULL;
+        }
+        else {
+            if(current->right->left != NULL) {
+                node* left;
+                node* temp_left;
+                temp_left = current->right;
+                left = current->right->left;
+                while(left->left != NULL) {
+                    temp_left = left;
+                    left = left->left;
+                }
+                current->data = left->data;
+                delete left;
+                temp_left->left = NULL;
+            }
+            else {
+                node* temp;
+                temp = current->right;
+                current->data = temp->data;
+                current->right = temp->right;
+                delete temp;
+            }
+        }
+        return true;
+    }
+    return true;
+}