লিংকড লিস্টকে K প্লেস ডান দিকে ঘুরানো (Rotate) C++-এ

#include 
using namespace std;

class ListNode{
public:
    int val;
    ListNode *next;
    ListNode(int data){
        val = data;
        next = NULL;
    }
};

ListNode* make_list(vector v){
    ListNode *head = new ListNode(v[0]);
    for(int i = 1; i < v.size(); i++){
        ListNode *ptr = head;
        while(ptr->next) ptr = ptr->next;
        ptr->next = new ListNode(v[i]);
    }
    return head;
}

void print_list(ListNode *head){
    ListNode *ptr = head;
    cout << "[";
    while(ptr->next){
        cout << ptr->val << ", ";
        ptr = ptr->next;
    }
    cout << "]" << endl;
}

class Solution {
public:
    ListNode* rotateRight(ListNode* head, int k) {
        if(!head) return head;
        int len = 1;
        ListNode* tail = head;
        while(tail->next){
            len++;
            tail = tail->next;
        }
        tail->next = head;
        k %= len;
        ListNode* newHead = NULL;
        for(int i = 0; i < len - k; i++){
            tail = tail->next;
        }
        newHead = tail->next;
        tail->next = NULL;
        return newHead;
    }
};

int main(){
    Solution ob;
    vector v = {1,2,3,4,5,6,7,8,9};
    ListNode *head = make_list(v);
    print_list(ob.rotateRight(head, 4));
    return 0;
}

[6, 7, 8, 9, 1, 2, 3, 4, ]