BSTIterator *bstIteratorCreate(struct TreeNode *root) {
BSTIterator *pstNode = NULL;
BSTIterator *pstCurNode = NULL;
BSTIterator *pstPreNode = NULL;
BSTIterator *pstPostNode = NULL;
if (NULL == root){
return NULL;
}
if (NULL != root->left){
pstPreNode = bstIteratorCreate(root->left);
}
pstCurNode = (BSTIterator *)malloc(sizeof(BSTIterator));
if (NULL == pstCurNode){
return NULL;
}
pstCurNode->next = NULL;
pstCurNode->val = root->val;
if (NULL != pstPreNode){
pstPreNode->next = pstCurNode;
pstNode = pstPreNode;
}else {
pstNode = pstCurNode;
}
if (NULL != root->right){
pstPostNode = bstIteratorCreate(root->right);
if (NULL != pstPostNode){
pstCurNode->next = pstPostNode;
}
}
return pstNode;
}
int main(int argc, char const *argv[])
{
int array[50] = {};
Tree T;
int i, Len, balanced;
Len = 50;
for (i = 0; i < Len; ++i)
array[i] = rand() % 100;
T = NULL;
for (i = 0; i < Len; ++i)
T = Insert(array[i], T);
PreOrderTraverse(T);
printf("\n");
struct BSTIterator *iter = bstIteratorCreate(T);
while (bstIteratorHasNext(iter))
printf("%d\n", bstIteratorNext(iter));
bstIteratorFree(iter);
return 0;
}
