有谁知道这个程序出了什么问题？

这个程序应该对二进制树节点进行插入、删除。问题是，当我在删除后显示树元素时，程序显示错误。请帮助我的程序中出现的错误。

#include <iostream.h>
#include <stdlib.h>
#include <string>
class Tnode
{
public:
    class Tnode *left;
    class Tnode *right;
    int info;
};
class tree: public Tnode
{
public:
    int top;
    Tnode *root;
    tree()
    {
        root=NULL;
        top=0;
    }
    void insert(int ch)
    {
        Tnode *temp,*temp1;
        if(root== NULL)
        {
            root=new Tnode;
            root->info=ch;
            root->left=NULL;
            root->right=NULL;
            return;
        }
        temp1=new Tnode;
        temp1->info=ch;
        temp1->right=temp1->left=NULL;
        temp=search(root,ch);
        if(temp->info>ch)
            temp->left=temp1;
        else
            temp->right=temp1;
    }
    Tnode *search(Tnode *temp,int ch)
    {
        if(root== NULL)
        {
            cout <<"no node present";
            return NULL;
        }
        if(temp->left==NULL && temp->right== NULL)
            return temp;
        if(temp->info>ch)
        {
            if(temp->left==NULL) return temp;
            search(temp->left,ch);
        }
        else
        { 
            if(temp->right==NULL) return temp;
            search(temp->right,ch);
        }
    }
    void display(Tnode *temp)
    {
        if(temp==NULL)
            return;
         display(temp->left);
         cout<<temp->info;
         display(temp->right);
    }
    Tnode *getposition(Tnode *root, int x)
    {  
        Tnode *temp;
        temp=root;
        while(temp&&temp->info != x)
            ((temp->info>x)?(temp=temp->left):(temp=temp->right));
        return(temp);
    }
    Tnode *getleft_right_most(Tnode *temp)
    { 
        Tnode *m=temp->left;
        while(temp->right)
            temp=temp->right;
            return temp;
    }
    Tnode *getfather(Tnode *root, Tnode *temp)
    {  
        Tnode *h=root;
        while(h->left!=temp&&h->right!=temp)
            ((h->info>temp->info)?h=h->left : h=h->right);
        return h;
    }
    Tnode *del(Tnode *temp, Tnode *f)
    {
        if(temp->left&&temp->right)
        if(temp->right)
        { 
            (f->left==temp)?f->left=temp->right : f->left=temp->right;
            temp->right=0;
        }
        if(temp->left)
        {
            (f->right==temp)?f->right=temp->left : f->right=temp->right;
            temp->left=0;
        }
        free(temp);
    }
    Tnode *delroot(Tnode *root)
    {  
        Tnode *d=root;
        if((d->right)&&!(d->left))
        { 
            root=d->right;
            d->right=0;
        }
        else if((d->left)&&!(d->right))
        { 
            root=d->left;
            d->left=0;
        }
        else
            root=0;
        return d;
    }
    Tnode *delprocess(Tnode *root, int key)
    {
        Tnode *d=root;
        Tnode *temp,*f,*t,*Re;
        if(root->info==key)
        {
            Re=delroot(d);
            return(Re);
        }
        else
        { 
            temp=getposition(d,key);
            if(temp->left!=0&&temp->right!=0)
            { 
                t=getleft_right_most(temp);
                temp->info=t->info;
                temp=t;
            }
            f=getfather(d,temp);
            Re=del(temp,f);
            return(Re);
        }
    }
};
main()
{
    tree t1;
    int ch,n,i;
    while(1)
    {
        cout <<"n1.INSERTn2.DELETE NUMBERn3.DISPLAYn4.EXITnEnter your                                       choice:";
        cin >> ch;
        switch(ch)
        {
        case 1:   do{
                 cout <<"nenter the elements you want to insert:";
                    cin >> ch;
                 cout<<"nto exit insert the number -1.";
                       if(ch!=-1)
                       t1.insert(ch);
                      }while(ch!=-1);
                        break;
        case 2:   t1.display(t1.root);break;
        case 3:    cout<<"nto delete a number of your insertion enter it : ";
                   cin>>n;
                 t1.root=t1.delprocess(t1.root,n);
                 cout<<"nthe tree after deletion is : ";
                 t1.display(t1.root); break;
        case 4:   exit(1);
        }
    }
}