Repository files navigation

The problem can be found at the following link:Question Link

• Create an unordered map mp to count the occurrences of each value in the linked list.
• Traverse the linked list using a pointer temp and update the map with the count of each node's data.
• Create a dummy node that points to the head of the linked list. This helps in handling edge cases where the head node might need to be removed.
• Initialize a pointer prev to the dummy node.
• Reset temp to the head of the linked list.
• Traverse the linked list again using temp.
• For each node, check the count of its data in the map:
• If the count is greater than 1, it means the node is a duplicate, so update the next pointer of prev to skip the current node (temp).
• If the count is 1, move the prev pointer to the current node (temp).
• Move the temp pointer to the next node.
• Set new_head to the next of the dummy node.
• Delete the dummy node to free up memory.
• Return new_head, which is the head of the modified linked list with duplicates removed.

• Time Complexity:O(N), whereN is the number of nodes in the linked list.
• Auxiliary Space Complexity:O(N), whereN is the number of nodes in the linked list.

classSolution {public:    Node*removeAllDuplicates(structNode* head)    {        unordered_map<int,int>mp;        Node* temp=head;while (temp)        {            mp[temp->data]++;            temp=temp->next;        }        Node* dummy=newNode(0);        dummy->next=head;        Node* prev=dummy;        temp=head;while (temp)        {if (mp[temp->data]>1)                prev->next=temp->next;else prev=temp;            temp=temp->next;        }        Node* new_head=dummy->next;delete dummy;return new_head;    }};

I always encourage contributors to participate in the discussion forum for this repository.

If you have a better solution or any queries / discussions related to theProblem of the Day solution, please visit ourdiscussion section. We welcome your input and aim to foster a collaborative learning environment.

If you find this solution helpful, consider supporting us by giving a⭐ star to thegetlost01/gfg-potd repository.