The following code is a AVL implementation, is a single-threaded code, but at run time appear such circumstance: directly on the ides of Devc++ compile operation cannot run over, I guess it is out of memory or access to the wild pointer, but can't find the problem; But a single step can correct operation, a great god can help me to point out problems, please? Thank you

 
# include 
#include  
using namespace std; 

Template 
Struct AVLTreeNode {
AVLTreeNode * _left; 
AVLTreeNode * _right; 
AVLTreeNode * _parent; 

K _key; 
V _value; 
Int _bf;//balance factor 

AVLTreeNode (const K& The key, const V& Value) 
: _key (key) 
, _value (value) 
, _left (NULL) 
, _right (NULL) 
, _parent (NULL) 
, _bf (0) 
{} 
}; 

Template 
The class AVLTree {
Typedef AVLTreeNode The Node; 
Public: 
AVLTree () 
: _root (NULL) 
{} 
Bool Insert (const K& The key, const V& Value) 
{
If (_root==NULL) 
{
_root=new Node (key, value); 
return true; 
} 
Node * cur=_root; 
The parent Node *=NULL; 
While (cur) 
{
If (cur - & gt; _key & gt; Key) 
{
The parent=cur; 
Cur=cur - & gt; _left; 
} 
Else if (cur - & gt; _key & lt; Key) 
{
The parent=cur; 
Cur=cur - & gt; _right; 
} 
The else 
{
return false; 
} 
} 
Cur=new Node (key, value); 
If (the parent - & gt; _key & gt; Key) 
{
The parent - & gt; _left=cur; 
Cur - & gt; _parent=parent; 
} 
The else 
{
The parent - & gt; _right=cur; 
Cur - & gt; _parent=parent; 
} 
//update balance factor 
//not balance, then rotate 
While (the parent) 
{
If (the parent - & gt; _right==cur) 
The parent - & gt; _bf + +; 
The else 
The parent - & gt; _bf -; 
//parent node balance factor is 0, the exit (on both sides of the parent node height, path length is the same, does not affect) 
If (the parent - & gt; _bf==0) 
break; 
//parent node balance factor to 1 or 1 (from 0 + 1 or from 0 to 1), on both sides of the parent node height is different, so need to continue to update balance factor 
Else if (the parent - & gt; _bf==1 | | the parent - & gt; _bf==1) 
{
Cur=parent; 
The parent=cur - & gt; _parent; 
} 
//parent node balance factor of 2 or 2, rotate 
The else//(the parent - & gt; _bf==2 | | the parent - & gt; _bf==2) rotate 
{
If (the parent - & gt; _bf==2) 
{
If (cur - & gt; _bf==1)//right single 
{
_RotateR (parent); 
} 
The else//(cur - & gt; _bf==1) single 
{
_RotateLR (parent); 
} 
} 
The else//(the parent - & gt; _bf==2) 
{
If (cur - & gt; _bf==1)//left single 
{
_RotateL (parent); 
} 
The else//(cur - & gt; _bf==1) right left single 
{
_RotateRL (parent); 
} 
} 
break; 
} 
} 
} 
The Node * Find (const K& Key) 
{
If (_root==NULL) 
return NULL; 
Node * cur=_root; 
While (cur) 
{
If (cur - & gt; _key & gt; Key) 
Cur=cur - & gt; _left; 
Else if (cur - & gt; _key & lt; Key) 
Cur=cur - & gt; _right; 
The else 
Return a cur. 
} 
return NULL; 
} 
Bool Remove (const K& Key) 
{
If (_root==NULL) 
return false; 

The parent Node *=NULL; 
Node * cur=_root; 
While (cur) 
{
If (cur - & gt; _key & gt; Key) 
{
The parent=cur; 
Cur=cur - & gt; _left; 
} 
Else if (cur - & gt; _key & lt; Key) 
{
The parent=cur; 
Cur=cur - & gt; _right; 
} 
The else 
{
Node * del; 
If (cur - & gt; _right==NULL) 
{
Del=cur; 
If (the parent==NULL) 
{
_root=cur - & gt; _left; 
//_root - & gt; _bf=0; 
} 
The else 
{
If (the parent - & gt; _left==cur) 
{
The parent - & gt; _left=cur - & gt; _left; 
The parent - & gt; _bf + +; 
} 
The else 
{
The parent - & gt; _right=cur - & gt; _left; 
The parent - & gt; _bf -; 
} 
} 
Delete the del. 
} 
Else if (cur - & gt; _left==NULL) 
{
Del=cur; 
If (the parent==NULL) 
{
_root=cur - & gt; _right; 
_root - & gt; _bf=0; 
Cout & lt; <"Cur:" & lt; } 
The else 
{
If (the parent - & gt; _left==cur) 
{
The parent - & gt; _left=cur - & gt; _right; 
The parent - & gt; _bf + +; 
} 
The else 
{
The parent - & gt; _right=cur - & gt; _right; 
The parent - & gt; _bf -; 
} 
} 
Delete the del. 
} 
The else 
{
The parent=cur; 
The Node * left=cur - & gt; _right; 
While (left - & gt; _left) 
{
The parent=left; 
Left=left - & gt; _left; 
} 
Del=left; 
Cur - & gt; _key=left - & gt; _key; 
Cur - & gt; _value=https://bbs.csdn.net/topics/left-> _value; 
If (the parent - & gt; _left==left) 
{
The parent - & gt; _left=left - & gt; _right; 
The parent - & gt; _bf + +; 
} 
The else 
{
The parent - & gt; _right=left - & gt; _right; 
The parent - & gt; _bf -; 
} 

Delete the del. 
} 
break; 
} 
} 
If (cur==NULL) 
{
return false; 
} 
While (the parent) 
{
If (the parent - & gt; _bf==0) 
{
break; 
} 
Else if (the parent - & gt; _bf==1 | | the parent - & gt; _bf==1) 
{
break; 
} 
The else//parent - & gt; _bf=2 | | the parent - & gt; _bf=2 
 -{
If (the parent - & gt; _bf==2) 
{
If (cur - & gt; _bf==1) 
_RotateR (parent); 
The else//cur - & gt; _bf=1 
_RotateLR (parent); 
} 
The else 
{
If (cur - & gt; _bf==1) 
_RotateL (parent); 
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