AVL tree insertion and deletion of nodes in C

This is my implementation of AVL tree, it works fine. is there any thing that can be improved about addition and deletion procedures specifically when deleting the root,

```
#include
#include
#include

typedef struct treenode node;

struct treenode
{
int value;
int height;
node *left;
node *right;
node *parent;
};

node *root = NULL;

int max(int a, int b)
{
if (a > b)
{
return a;
}
else
{
return b;
}
}

int nodetype(node *ptr,int flag=1)
{
//please ignore the default argument for now
/Determines type of node. ex. leaf or internal/
if ((ptr->parent == NULL)&&(flag))
{
return 1;
//root
}
else if ((ptr->left == NULL) && (ptr->right == NULL))
{
return 2;
//leaf node
}
else if (ptr->left == NULL)
{
return 3;
//internal node with right child
}
else if (ptr->right == NULL)
{
return 4;
//internal node with left child
}
else
{
return 5;
//internal node with left and right childs
}

}

int childtype(node *ptr)
{
/Determine wether ptr is left child of its parent or right child/
node *temp = ptr->parent;

if (temp->left == ptr)
{
return 1;
//left child
}
else if (temp->right == ptr)
{
return 2;
//right child
}
}

node* createnode(int value)
{
node ptr = (node)malloc(sizeof(node));
ptr->left = ptr->right = ptr->parent = NULL;
ptr->value = value;
ptr->height = 0;
return ptr;
}

node getposition(node ptr, int value)
{
/Return address of the first node having value equal to "value", returns NULL if not found/
if (ptr == NULL)
{
return NULL;
}
else if (value value)
{
return getposition(ptr->left, value);
}
else if (value > ptr->value)
{
return getposition(ptr->right, value);
}
else
{
return (ptr);
}

}

in

StackExchange Code Review Q#135375, answer score: 3