83. Remove Duplicates from Sorted List

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* deleteDuplicates(ListNode* head) {
        if(head == NULL)
            return head;
        
        ListNode* curr = head;

        while( curr != NULL)
        {
            if((curr -> next != NULL)&&(curr -> val == curr -> next -> val))
            {
                ListNode* next_next = curr -> next -> next;
                ListNode* nodeToDelete = curr -> next;
                delete(nodeToDelete);
                curr -> next = next_next;
            }
            else
            {
                curr = curr -> next;
            }
        }

        return head;
    }
};