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Map not loading correctly?

Imagine (9)
For my BST-tree based map, whenever I load in my data from a file, it reads everything in, but the only thing that actually stays in the tree is the most recent element read. I don't know why it's doing this, as when I was dealing with integers, it read in and balanced them correctly. Can anyone identify the problem?

File I'm reading in:
http://www.june29.com/IDP/files/Spanish.txt

Code for reading in the file:
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void Map<K,V>::loadFromFile(string file) {
    
    ifstream tmp;
    K tmp1;
    V tmp2;
    tmp.open(file.c_str());
    string discard;
    string junk;
    tmp >> discard;
    cout << discard << endl;
    while(true) {
        getline(tmp,junk);
        if (junk == discard)
            break;            
    }
    int i = 0;
    while(!tmp.eof()) {
        if (i == 5)
            break;        
        tmp >> tmp1;
        getline(tmp, tmp2);
        insert(tmp1, tmp2);
        ++i;
    }
    tmp.close();
    
}


Insertion:
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template <typename K, typename V>
void Map<K,V>::insert(const K& k, const V& v) {

    if (key !="") {
        key = k;
        value = v;
        return;
    }
    
    if(k == key)
        return;
    
    if (k < key)
        if (left != NULL)
            left->insert(k, v);
            
        else {
            left = new Map<K,V>;
            left->key = k;
            left->value = v; 
            left->left = NULL;
            left->right =NULL;           
        }
        
    else
        if (right != NULL)
            right->insert(k,v);
        
        else {
            right = new Map<K,V>;
            right->key = k;
            right->value = v; 
            right->left = NULL;
            right->right =NULL;
        }
        
    balance();
}


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Left Rotation + Right Rotation + Balance function:
template <typename K, typename V>
void Map<K,V>::shiftLeft() {
        
    //so much work to maintain access to the root node
    if(!left)
        return;
    Map* tmp1 = right;
    Map* tmp2 = left->right;
    right = NULL;
    left->right = NULL;
    swap(left);
    right = left;
    left = left->left;
    right->right = tmp1;
    right->left = tmp2;
    
}

template <typename K, typename V>
void Map<K,V>::shiftRight() {
    if(!right)
        return;        
    Map* tmp1 = right->left;
    Map* tmp2 =left;
    right->left = NULL;
    left = NULL;
    swap(right);
    left = right;
    right = right-> right;
    right->left = tmp2;
    right->right = tmp1;
    
}

template <typename K, typename V>
void Map<K,V>::balance() {
    
    if(!this)
        return;
        
    if(balanceFactor() == -2)
        if(right->balanceFactor() == -1)
            shiftLeft();
        
        else if(right->balanceFactor() == 1) {
            right->shiftRight();
            shiftLeft();
        }
        
        else if(right->balanceFactor() == -2)
            right->balance();
            
        else if(right->balanceFactor() == 2)
            left->balance();
            
        else
            cout << "YOU DUN GOOFED" << endl;
            
    else if(balanceFactor() == 2)
        if (left->balanceFactor() == 1)
            shiftRight();
            
        else if(left->balanceFactor() == -1) {
            left->shiftLeft();
            shiftRight();
        }
        
        else if(left->balanceFactor() == 2)
            left->balance();
        
        else if(left->balanceFactor() == -2)
            right->balance();
        
        else
            cout << "YOU DUN GOOFED" << endl;
    
    //allows me to recursively balance the tree;
    left->balance();
    right->balance();            

}


What is displayed when I run the program:
aardvarks osos hormigueros

Why am I deleting everything else?
Last edited on
ne555 (10692)
Your code is obfuscated.
Consider using better names than `tmp{,1,2}'
Use the constructor to initialize the members
Comment it.

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swap(left); //¿just one argument? ¿swap with what?
//...
if(!this) //¿how can this happen?
   return;


Get a debugger, execute step by step in the reading while looking at your map structure.
Imagine (9)
swap() has an implicit parameter, and I don't know how to use a debugger.
Zhuge (4664)
Please describe how your swap() works then.

Learn to use one. It will help you a lot.
Imagine (9)
Let's say MapA has:
key = a
value = b

MapB:
key = c
value = d

when I do MapA.swap(MapB);
I have a temp variable to hold the key, and another to hold the value of Map B.
MapB->key = a;
MapB->value = b;
key = the temp key var;
value = the temp value var;
Because I'm calling key and value inside a function where the implicit parameter is MapA, the compiler knows that I'm calling key and value on it.
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