【leetcode 簡單】 第五十七題 刪除鏈表中的節點

刪除鏈表中等於給定值 val 的所有節點。

示例:

輸入: 1->2->6->3->4->5->6, val = 6
輸出: 1->2->3->4->5

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     struct ListNode *next;
 * };
 */

struct ListNode* removeElements(struct ListNode* head, int val) {
    struct ListNode* s = (struct ListNode* )malloc(sizeof(struct ListNode));
    s->next = head;
    
    struct ListNode* pre = s;
    struct ListNode* cur = head;
    while (cur)
    {
        if (cur->val == val)
        {
            pre->next = cur->next;
        }
        else
        {
            pre = cur;
        }
        cur = cur->next;
    }
    return s->next;
}