Flattening linked list problem

[RER_CODER]

Hey There, This is RER, I am new to coding and I was solving the flattening the linkedlist problem on the geeks for geeks, and I am getting weird output and I am unable to debug , so the Problem is

and I my code looks like this

 Node *flatten(Node *root) {
        // Your code here
        Node* ret = root;
        Node* start = root;
        while(start!=NULL)
        {
            //cout << start->data << endl;
            Node* temp = root->next;
            Node* moving = root->bottom;
            while(moving!= NULL && temp!= NULL && temp->data < moving->data)
            {
                
                if(root== NULL)
                {
                    break;
                }
                
                if(temp== NULL)
                {
                    break;
                }
                //cout << "moving " << root->data << endl;
                //cout << "temp "<< temp->data << endl;
                root = root->next;
                temp = temp->next;
            }
            if(root && moving){
            //cout << moving->data << "ins set" << endl;
            //cout << "root next" << root->data << endl;
            if(!temp)
            {
                //cout << "its null so setting null" << endl;
            }
            
            root->next = moving;
            moving->next = temp;
            }
            root = start->next;
            if(root!=NULL){
            //cout << "root val" << root->data << endl;
            }
            start = start->next;
        }
        // while(ret)
        // {
        //     cout << ret->data << endl;
        //     ret = ret->next;
        // }
        return ret;
    }

and weirdly enough , when I printed the linked list , I am getting proper out put you can see the end while loop for printing the list

but when removed , I am getting this

I know solution will be something stupid thing I have done, but requesting anyone looking to please help....
I am unable to figure out ..

I am new to forums so anyone can openly criticize my way of asking , if you find it wrong..

Thanks in advance..

 

[WhiteCube]

Your output uses the next pointer.

Their output routine uses the bottom pointer, as stated on page 1.

I have not digested your program yet, this is just my first impression.

 

[WhiteCube]

Your solution is interesting, that would not have been my first approach.

I would have worked from right to left, merging 2 vertical lines at a time, like a zipper.

 

[RER_CODER]

Your output uses the next pointer.

Their output routine uses the bottom pointer, as stated on page 1.

I have not digested your program yet, this is just my first impression.

Hii , Very Thank you for your solution , in the first minds, I would have done like storing the variables and then then sort them in the array then populate them as it is , but I want to kind a play with the linked lists , so I tried no memory approach..

your reply was helpfuil , knowing , I was trying to populate next instead of bottom , it was dumb of me...
Thanks for pointing that...

//{ Driver Code Starts
#include <bits/stdc++.h>
using namespace std;

struct Node {
int data;
struct Node *next;
struct Node *bottom;

Node(int x) {
data = x;
next = NULL;
bottom = NULL;
}
};

void printList(Node *Node) {
while (Node != NULL) {
printf("%d ", Node->data);
Node = Node->bottom;
}
printf("\n");
}


// } Driver Code Ends
/* Node structure used in the program

struct Node{
int data;
struct Node * next;
struct Node * bottom;

Node(int x){
data = x;
next = NULL;
bottom = NULL;
}

};
*/

class Solution {
public:
// Function which returns the root of the flattened linked list.
Node *flatten(Node *root) {
Node* l1 = root;
Node* l2;
Node* l3;
Node* totalStart = l1;

if(root->next)
{
l2 = root->next;
}
else
{
l2 = NULL;
return root;
}
if(root->next && root->next->next)
{
l3 = root->next->next;
}
else{
l3 = NULL;
}
l1->next = NULL;
Node* temp;
//cout << l1->data << endl;
while(l1!=NULL && l2!=NULL){
totalStart = l1;
if(l1->data > l2->data)
{
temp = l2;
l2 = l1;
l1 = temp;
totalStart = l1;
}
l1->next = NULL;
while(l1!= NULL && l2!= NULL)
{
//Node* temp2;
Node* back = l1;
l1 = l1->bottom;
while(l1!= NULL && l2!= NULL && l1->data <= l2->data)
{
//cout << l1->data << endl;
back = back->bottom;
l1 = l1->bottom;
}
back->bottom = l2;
temp = l1;
l1 = l2;
l2 = temp;
// back->next = l2;
// temp = l1;
// l1 = l2;
// l2 = temp;

}
l1 = totalStart;
l2 = l3;
if(l3){
l3 = l3->next;
}
}
return totalStart;
}
};


//{ Driver Code Starts.

int main() {
int t;
cin >> t;
while (t--) {
int n;
vector<int> work;
string input;
getline(cin, input); // Read the entire line for the array elements
getline(cin, input); // Read the entire line for the array elements
stringstream ss(input);
int number;
while (ss >> number) {
work.push_back(number);
}
n = work.size();

Node *head = NULL;
Node *pre = NULL;

for (int i = 0; i < n; i++) {
int m = work - 1;
int data;
cin >> data;
Node *temp = new Node(data);
if (head == NULL) {
head = temp;
pre = temp;
} else {
pre->next = temp;
pre = temp;
}

Node *preB = temp;
for (int j = 0; j < m; j++) {
int temp_data;
cin >> temp_data;
Node *tempB = new Node(temp_data);
preB->bottom = tempB;
preB = tempB;
}
}

Solution ob;
Node *root = ob.flatten(head);
printList(root);
}
return 0;
}

// } Driver Code Ends

 

[RER_CODER]

since it was laptop , I didn't get notifications , sorry for the late response....