LeetCode Problem : Remove Duplicates from Sorted List

Problem

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.

Code

ListNode *deleteDuplicates(ListNode *head) {
    // IMPORTANT: Please reset any member data you declared, as
    // the same Solution instance will be reused for each test case.
    if(!head)
    return head;
    ListNode *prev = head;
    while(prev){
        ListNode *curr = prev->next;
        while(curr && prev->val == curr->val)
            curr = curr->next;
        prev->next = curr;
        prev = curr;
    }
    return head;

}