int deleteHelper(trieNode_t *pNode, char key[], int level, int len)
{
if( pNode )
{
// Base case
if( level == len )
{
if( pNode->eos )
{
// Unmark leaf node
pNode->eos = 0;
// If empty, node to be deleted
if( isItFreeNode(pNode) )
{
return 1;
}
return 0;
}
}
else // Recursive case
{
int index = key[level]-'a';
if( deleteHelper(pNode->child[index], key, level+1, len) )
{
// last node marked, delete it
FREE(pNode->child[index]);
// recursively climb up, and delete eligible nodes
return ( !leafNode(pNode) && isItFreeNode(pNode) );
}
}
}
return 0;
}
bool deleteHelper(trie_node_t *pNode, char key[], int level, int len)
{
if( pNode )
{
// Base case
if( level == len )
{
if( pNode->value )
{
// Unmark leaf node
pNode->value = 0;
// If empty, node to be deleted
if( isItFreeNode(pNode) )
{
return true;
}
return false;
}
}
else // Recursive case
{
int index = INDEX(key[level]);
if( deleteHelper(pNode->children[index], key, level+1, len) )
{
// last node marked, delete it
FREE(pNode->children[index]);
// recursively climb up, and delete eligible nodes
return ( !leafNode(pNode) && isItFreeNode(pNode) );
}
}
}
return false;
}