leetcode[203]:Remove Linked List Elements

Remove Linked List Elements

Remove all elements from a linked list of integers that have value val.

Example

Given: 1 –> 2 –> 6 –> 3 –> 4 –> 5 –> 6, val = 6

Return: 1 –> 2 –> 3 –> 4 –> 5

Credits:

Special thanks to @mithmatt for adding this problem and creating all test cases.

/**
* Definition for singly-linked list.
* struct ListNode {
*     int val;
*     struct ListNode *next;
* };
*/
struct ListNode* removeElements(struct ListNode* head, int val) {

struct ListNode *L,*tmp;
tmp =  (struct ListNode*) malloc( sizeof( struct ListNode* ) );
if(head == NULL ) return head;
while(head->val == val)
{
head=head->next;
if(head == NULL ) return head;
}
L=head;
while(L->next != NULL){
if(L->next->val == val)
{
tmp = L->next;
L->next = tmp->next;
free(tmp);
}
else  L = L->next;
}

return head;
}

空链表！！！起始为空，或是删除后为空！！！