Hi all,
i have this struct for a binary tree node
typedef struct treenode
{
char *word;
struct treenode *right;
struct treenode *left;
}TreeNode;
and to the element *word, i dynamically allocate memory for it as below
(and also for the TreeNode too)
addNode(TreeNod e*,char*);
char *token, buf[BUF_MAX], *memWord;
TreeNode *root;
/*do memory allocation check */
while((fgets(bu f,BUF_MAX,fileP tr)) != NULL)
{
/* do buffer handling here */
token = strtok(buf,"\n" );
while (token != NULL)
{
/* is the following right ? */
memWord = malloc(sizeof(c har) * strlen(token);
strcpy(memWord, token);
addNode(root,me mWord);
token = strtok(NULL, "\n");
}
}
the code above reads a line from a file and then tokenizes the line
read into tokens and then allocates memory in the same length of the
token, then copies the token into memWord and passes to a function to
add it to the BST pointed by root.
My question and problem is that , when i delete a node from the list
and free the memory for both the word inside the node and the node
itself, i get no memory leaks or whatsoever (because according to
valgrind i have more free's then allocations) and then print them out
(in-order), well, i get weird characters and mumble jumble for insted
of words. But if i dont free the word inside the node (and get some
memory leaks) then print them out it actually works, i.e the nodes that
deleted are gone and there is no weird characters and all. So anyway
here is the code that i use to delete a node (recursive)
delete(char *w, TreeNode T)
{
TreeNode tmpNode;
if (T == NULL)
return T;
if (strcmp(w, T->word) < 0 )
T->left = delete(w,T->left);
else
if (strcmp(w, T->word) > 0)
T->right = delete(w,T->right);
else
{
if(T->left && T->right)
{
tmpNode = findMin(T->right);
T->word = tmpNode -> word;
T->right = delete(w,T->right);
}
else
{
tmpNode = T;
if (T->left == NULL)
T= T->right;
else if (T->right == NULL)
T= T->left;
free(tmpNode->word);
free(tmpNode);
}
}
return T;
}
i have this struct for a binary tree node
typedef struct treenode
{
char *word;
struct treenode *right;
struct treenode *left;
}TreeNode;
and to the element *word, i dynamically allocate memory for it as below
(and also for the TreeNode too)
addNode(TreeNod e*,char*);
char *token, buf[BUF_MAX], *memWord;
TreeNode *root;
/*do memory allocation check */
while((fgets(bu f,BUF_MAX,fileP tr)) != NULL)
{
/* do buffer handling here */
token = strtok(buf,"\n" );
while (token != NULL)
{
/* is the following right ? */
memWord = malloc(sizeof(c har) * strlen(token);
strcpy(memWord, token);
addNode(root,me mWord);
token = strtok(NULL, "\n");
}
}
the code above reads a line from a file and then tokenizes the line
read into tokens and then allocates memory in the same length of the
token, then copies the token into memWord and passes to a function to
add it to the BST pointed by root.
My question and problem is that , when i delete a node from the list
and free the memory for both the word inside the node and the node
itself, i get no memory leaks or whatsoever (because according to
valgrind i have more free's then allocations) and then print them out
(in-order), well, i get weird characters and mumble jumble for insted
of words. But if i dont free the word inside the node (and get some
memory leaks) then print them out it actually works, i.e the nodes that
deleted are gone and there is no weird characters and all. So anyway
here is the code that i use to delete a node (recursive)
delete(char *w, TreeNode T)
{
TreeNode tmpNode;
if (T == NULL)
return T;
if (strcmp(w, T->word) < 0 )
T->left = delete(w,T->left);
else
if (strcmp(w, T->word) > 0)
T->right = delete(w,T->right);
else
{
if(T->left && T->right)
{
tmpNode = findMin(T->right);
T->word = tmpNode -> word;
T->right = delete(w,T->right);
}
else
{
tmpNode = T;
if (T->left == NULL)
T= T->right;
else if (T->right == NULL)
T= T->left;
free(tmpNode->word);
free(tmpNode);
}
}
return T;
}
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