C doubly linked list - c

Question

I am trying to implement (BST) with doubly linked list in C with loops. but something I couldn't understand why one could is work as expected and the other is not.
look at first code which is working well.
#include<stdio.h>
#include<stdlib.h>
typedef struct Node {
int data;
struct Node* left;
struct Node* right;
} Node;
typedef struct BST {
Node* root;
}BST;
Node * createNode(int value) {
Node * a= (Node* )malloc(sizeof(Node));
a->left = NULL;
a->right = NULL;
a->data = value;
return a;
}
void printBST(Node * bst) {
if(bst == NULL) {return; }
printf("%d ", bst->data);
printBST(bst->left);
printBST(bst->right);
}
Node* createRandomBST(size_t len){
if(len == 0) {return NULL;}
Node* tempBST = createNode(rand()%200);
printf(" root: %d \n", tempBST->data);
Node* ptr_1;
Node *ptr_2;
ptr_1 = tempBST;
ptr_2 = tempBST;
for(int i = 0; i < len; i++) {
int value = i*i+22;
tempBST = ptr_1;
while (1)
{
if(value >= tempBST->data) {
if(tempBST->right == NULL) {
tempBST->right = createNode(value);
printf("right-I: %d, value:%d \n", i, tempBST->data);
break;
}
tempBST = tempBST ->right;
}else {
if(tempBST->left == NULL) {
tempBST->left = createNode(value);
printf("left-I: %d, value:%d \n", i, value);
break;
}
tempBST= tempBST->left;
}
}
}
return ptr_2;
}
Second code which isn't working as expected.
#include<stdio.h>
#include<stdlib.h>
typedef struct Node {
int data;
struct Node* left;
struct Node* right;
} Node;
typedef struct BST {
Node* root;
}BST;
Node * createNode(int value) {
Node * a= (Node* )malloc(sizeof(Node));
a->left = NULL;
a->right = NULL;
a->data = value;
return a;
}
void printBST(Node * bst) {
if(bst == NULL) {return; }
printf("%d ", bst->data);
printBST(bst->left);
printBST(bst->right);
}
Node* createRandomBST(size_t len){
if(len == 0) {return NULL;}
Node* tempBST = createNode(rand()%200); //start by creating root node.
printf(" root: %d \n", tempBST->data); // print the root node
Node* ptr_1;
Node *ptr_2;
ptr_1 = tempBST; // ptr_1 and ptr_2 are copy of the root node.
ptr_2 = tempBST;
for(int i = 0; i < len; i++) { // start the loop -- tempBST , ptr_1 and ptr_2 are all pointing to the root node
int value = i*i+22; //the value needed to be inserted.
tempBST = ptr_1; // every time need to insert a node it will start from the root node.
while (1) //loop until insertion is happend
{
if(value >= tempBST->data) { //if the value greater than the root->data then go right
tempBST = tempBST ->right; // now tempBST is pointing to tempBST->right not the root
if(tempBST == NULL) { //if tempBST is null then the insertion will happened else loop with tempBST-> as the root..
tempBST = createNode(value); //if tempBST->right is empty insert the node.
printf("right-I: %d, value:%d \n", i, tempBST->data);
break; break;
}
}else { //if the value greater than the root->data then go left
tempBST = tempBST ->left; // now tempBST is pointing to tempBST->left not the root
if(tempBST == NULL) {
tempBST = createNode(value); //if tempBST->left is null then the insertion will happened else loop with tempBST-> as the root..
printf("left-I: %d, value:%d \n", i, value);
break;
}
}
}
}
return ptr_2; //return a pointer the root;
}
int main() {
Node* tem;
tem = createRandomBST(20);
printf("%d ", tem->data);
printBST(tem);
}
I tried to debug it with GDB I couldn't understand the problem.
in the first code the printBST() print all the nodes but in the second one only the root is being printed