Hello Community, So today I solved some questions on LinkedList.

Hello Community, So today I solved some questions on LinkedList.
1. Remove Duplicates from Sorted LinkedList

public ListNode deleteDuplicates(ListNode node) {
        if(node == null){
            return node;
        }
        ListNode head = node;
        while(node.next != null){
            if(node.val == node.next.val){
                node.next = node.next.next;
            } else {
                node = node.next;
            }       
        }
        return head;
    }

2. Merge Two Sorted LinkedLists.

public ListNode mergeTwoLists(ListNode list1, ListNode list2) {
        ListNode dummyHead = new ListNode();
        ListNode tail = dummyHead;

        while(list1 != null && list2 != null){
            if(list1.val <= list2.val){
                tail.next = list1;
                list1 = list1.next;
                tail = tail.next;
            } else {
                tail.next = list2;
                list2 = list2.next;
                tail = tail.next;
            }
        }
        while(list1 != null){
            tail.next = list1;
            list1 = list1.next;
            tail = tail.next;
        }
        while(list2 != null){
            tail.next = list2;
            list2 = list2.next;
            tail = tail.next;   
        }
        return dummyHead.next;
    }

3. Detect the LinkedList Cycle

public boolean hasCycle(ListNode head) {
         if(head == null){
                return false;
            }
        ListNode fast = head;
        ListNode slow = head;

        while(fast.next != null && fast.next.next != null ){
            fast = fast.next.next;
            slow = slow.next;
            if(fast==slow){
                return true;
            }
        }
        return false;
    }

4. Detect where the LinkedList cycle is starting.

public int lengthOfCycle(ListNode head){
        ListNode fast = head;
        ListNode slow = head;

        while(fast != null && fast.next != null ){
            fast = fast.next.next;
            slow = slow.next;
            if(fast==slow){
                ListNode temp = slow;
                int cnt = 0;
                do{
                    temp = temp.next;
                    cnt++;
                } while (temp != slow);
                return cnt; 
            }
        }
        return 0;
    }
    public ListNode detectCycle(ListNode head) {
        int length = 0;
        ListNode fast = head;
        ListNode slow = head;

        while(fast!= null && fast.next != null ){
            fast = fast.next.next;
            slow = slow.next;
            if(fast==slow){
            length = lengthOfCycle(head);
            break;
            }
        }

        if(length == 0) return null;

        ListNode f = head;
        ListNode s = head;
        while(length > 0){
            s = s.next;
            length--;
        }
        while(f != s){
            f=f.next;
            s=s.next;
        }
        return s;
    }

5. Happy Number

public boolean isHappy(int n) {
        int slow = n;
        int fast = n;

        do{
            slow = calculate(slow);
            fast = calculate(calculate(fast));
         } while(slow != fast);

        if(slow == 1) return true;
        return false;
    }
    public int calculate(int n){
        int ans = 0;
        while(n>0){
            int rem = n%10;
            ans += rem*rem;
            n = n/10;
        }
        return ans;
    }

6. Find middle of LinkedList.

 public ListNode middleNode(ListNode head) {
        ListNode slow = head;
        ListNode fast = head;

        while(fast != null && fast.next != null){
            fast = fast.next.next;
            slow = slow.next;
        }
        return slow;

    }

Today it's my first blog on HshNode..
I will try to post a blog consistently on Hashnode.
Now I will try to upload all my sharings and learnings in DSA and development whatever I will do.I will invite folks from the community to come up along with me and let us post our daily learnings with everyone.