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POBinary Search Tree LNK2019 and LNK1120 errors
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copied!<p>I've been working on a class project where we have to add an insert, count, remove_max and remove_all function to a binary search tree implementation given to us by the instructor. I've gotten down all of the functions, but for some reason I'm getting these two errors:</p> <pre><code>1>bagexam.obj : error LNK2019: unresolved external symbol "public: __thiscall main_savitch_10::bag<int>::bag<int>(void)" (??0?$bag@H@main_savitch_10@@QAE@XZ) referenced in function "int __cdecl test1(void)" (?test1@@YAHXZ) 1>C:\Users\Filip\Documents\Visual Studio 2012\Projects\Project 3\Debug\Project 3.exe : fatal error LNK1120: 1 unresolved externals </code></pre> <p>And when I double click or "Go to Location" on these errors, it doesn't take me anywhere... so I can't tell where the problem is stemming from. Here is the code that I implemented:</p> <p>insert:</p> <pre><code>template <class Item> void bag<Item>::insert(const Item& entry) // Header file used: bintree.h { binary_tree_node<Item> *cursor; if (root_ptr == NULL) { // Add the first node of the binary search tree: root_ptr = new binary_tree_node<Item>(entry); return; } else { // Move down the tree and add a new leaf: cursor = root_ptr; binary_tree_node<Item> *insert_ptr; insert_ptr = new binary_tree_node<Item> (entry); bool finished = false; while(!finished) { if (cursor->data() < entry) { if (cursor->right() == NULL) //Check if this this the largest node of the subtree? { cursor -> right() = insert_ptr; //Add to the right side. finished = true; } cursor = cursor -> right(); } else // entry < (cursor -> data) { if (cursor->left() == NULL) { cursor->left() = insert_ptr; //Add to the left side. finished = true; } cursor=cursor->left(); } } } } </code></pre> <p>count:</p> <pre><code>template <class Item> typename bag<Item>::size_type bag<Item>::count(const Item& target) const { size_type answer = 0; binary_tree_node<Item> *cursor; cursor = root_ptr; if (root_ptr == NULL) return 0; //it's empty so return 0 else { while(cursor!=NULL) { if(cursor->data() < target) //if target is bigger, go to the right cursor=cursor->right(); else if(cursor->data() > target) //target is smaller, go left cursor=cursor->left(); else if(cursor->data() == target) //Did we find one? { answer++; //We found one cursor=cursor->left(); //Go left, there might be another down there } else cout << "Houston we have a problem!" << endl; } } return answer; } </code></pre> <p>remove_max:</p> <pre><code>template <class Item> void bst_remove_max(binary_tree_node<Item>*& root_ptr, Item& removed) // Precondition: root_ptr is a root pointer of a non-empty binary // search tree. // Postcondition: The largest item in the binary search tree has been // removed, and root_ptr now points to the root of the new (smaller) // binary search tree. The reference parameter, removed, has been set // to a copy of the removed item. { if (root_ptr == NULL) { return; } else if( root_ptr -> right() == NULL) { removed = root_ptr -> data(); binary_tree_node <Item>* to_delete = root_ptr; root_ptr = root_ptr -> left(); delete to_delete; } else { bst_remove_max(root_ptr -> right(), removed); } } </code></pre> <p>remove_all:</p> <pre><code>template <class Item> typename bag<Item>::size_type bst_remove_all (binary_tree_node<Item>*& root_ptr, const Item& target) // Precondition: root_ptr is a root pointer of a binary search tree // or may be NULL for an empty tree). // Postcondition: All copies of target have been removed from the tree // has been removed, and root_ptr now points to the root of the new // (smaller) binary search tree. The return value tells how many copies // of the target were removed. { binary_tree_node<Item> *oldroot_ptr; if (root_ptr == NULL) { // Empty tree return 0; } if (target < root_ptr->data( )) { // Continue looking in the left subtree bst_remove(root_ptr -> left(), target); } if (target > root_ptr->data( )) { // Continue looking in the right subtree bst_remove(root_ptr -> right(), target); } if (root_ptr->left( ) == NULL) { // Target was found and there is no left subtree, so we can // remove this node, making the right child be the new root. oldroot_ptr = root_ptr; root_ptr = root_ptr->right( ); delete oldroot_ptr; return 1; } // If code reaches this point, then we must remove the target from // the current node. We'll actually replace this target with the // maximum item in our left subtree. We then continue // searching for more copies of the target to remove. // This continued search must start at the current root (since // the maximum element that we moved up from our left subtree // might also be a copy of the target). bst_remove_max(root_ptr->left( ), root_ptr->data( )); return 1 + bst_remove_all(root_ptr, target); } </code></pre> <p>I can't imagine the problem being anywhere else besides the functions that we had to write. Otherwise, there is a header file for the bag, a header for the tree and a test cpp file all provided for us and left unchanged by me.</p> <p>Thanks guys, let me know if you need any more info on the program, and I apologize for posting so much code, I just don't know where to look or what is pertinent to solving this problem as I can't understand the errors :/</p>

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