LEET code--Remove Duplicates from Sorted List

Remove Duplicates from Sorted List

 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.


current 只有再future不一樣的時候才會前進
future會每次循環都向前

這樣是避免連續出現同樣數字，保留current的  讓future去找誰重複
如果沒有重複就current向前

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struct ListNode* deleteDuplicates(struct ListNode* head) { if(head==NULL)return head; struct ListNode *current=head; struct ListNode *future=head->next; while(current!=NULL && future!=NULL){ if(current->val == future->val){ current->next=future->next; free(future); future=(current !=NULL) ? current->next: NULL; } else{ current=current->next; future=(current !=NULL) ? current->next: NULL; } } return head; }