LeetCode 203: Remove Linked List Elements

LeetCode Linked List

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.

思路

两个指针, 一样的就删, 不一样就next.

代码

C语言版本：

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     struct ListNode *next;
 * };
 */
struct ListNode* removeElements(struct ListNode* head, int val) {
    struct ListNode* dummy;
    dummy -> next = head;
    struct ListNode* p = dummy;  
    struct ListNode* q = head;
    while(q != NULL) {  
        if(q->val == val) {  
            p->next = q->next;  
        } else {  
            p = p->next;  
        }  
        q = q->next;  
    }  
          
    return dummy->next; 
}

63 / 63 test cases passed.
Status: Accepted
Runtime: 12 ms

st=>start: Start
e=>end
op=>operation: My Operation
cond=>condition: Yes or No?

st->op->cond
cond(yes)->e
cond(no)->op

Alice->Bob: Hello Bob, how are you?
Note right of Bob: Bob thinks
Bob-->Alice: I am good thanks!