my program crashes after running

well this is my code and basically what i am trying to do is for my program to take words out of a text file that i prepared and to pass it to my program and count the amount of unique words, and to print out the unique word with the count on the side of it. i have cleared up all the errors i had but now i am stuck as it crashes every time i try to run it. i would appreciate if someone could enlighten me on where i have done wrong on.

#include <iostream>
#include <cstdlib>
#include <fstream>

using namespace std;


class BST
{
public:
    BST ();

    void insert (char*);
    void printBST () const;
    bool findNode (char*) const;

private:
    struct Node;
    typedef Node* NodePtr;

    struct Node
    {
    char *word;
    int count;
    NodePtr left, right;
    };

    NodePtr root;

    int compareVP (char*, char*) const;
    void insert (NodePtr&, char*);
    void inorderPrint (NodePtr) const;
    bool findNode (NodePtr, char*) const;
};

int main ()
{
BST t;
    char* word;
    ifstream readfile("infile.txt");
    if(!readfile)
        {
    cout << "File could not be opened/found";
    return 0;
    }    
while(readfile>> word)
    {
        t.insert(word);
    }   
if(readfile.eof())  
t.printBST ();
}

BST::BST ()
{
root = NULL;
}

void BST::insert (char* word)
{
insert (root, word);
}

void BST::printBST () const
{
inorderPrint (root);
}

bool BST::findNode (char* word) const
{
return findNode (root, word);
}

int BST::compareVP (char* item1, char* item2) const
{
char* value1 = item1;
char* value2 = item2;

if (strcmp(value1,value2)==0)
    return 0;
else if (strcmp(value1,value2)>0)
    return 1;
else
    return -1;
}

void BST::insert (NodePtr& root, char* word)
 {
if (root == NULL)
{
    NodePtr temp = new Node;
    temp -> word = word;
    temp -> left = NULL;
    temp -> right = NULL;

    root = temp;
}
else if (compareVP (root -> word, word) > 0)
    insert (root -> left, word);
else if (compareVP (root -> word, word) < 0)
    insert (root -> right, word);
else if (compareVP (root -> word, word) == 0)
    root -> count++;
}

void BST::inorderPrint (NodePtr root) const 
{
cout << "Word\tCount\n";
if (root != NULL)
{
    inorderPrint (root -> left);
    cout << root -> word << "\t";
    cout << root -> count << "\n";
    inorderPrint (root -> right);
}
else
    cout << endl;
}


bool BST::findNode (NodePtr root, char* word) const
{
if (root == NULL)
    return false;
else
{
    int k = compareVP (root -> word, word);

    if (k == 0)
        return true;
    else if (k > 0)
        return findNode (root -> left, word);
    else
        return findNode (root -> right, word);
}
}