Leetcode：203 Remove Linked List Elements（删除链表中的某个元素））

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.

递归实现：

if (head == null) return null;
head.next = removeElements(head.next, val);
if( head.val == val )
return head.next ;
else {
return head;
}

迭代：

while (head != null && head.val == val){
head = head.next;
}
ListNode currNode = head;
while (currNode != null && currNode.next != null){
if (currNode.next.val == val)
currNode.next = currNode.next.next;
else
currNode = currNode.next;
}
return head;