203. Remove Linked List Elements
解析
第一次: 2.29%第二次:100%。我真的不解.等我学会了性能检测,就来一探究竟
solution1:
class Solution {
public:
ListNode* removeElements(ListNode* head, int val) {
ListNode dummy(-1);
dummy.next = head;
ListNode* stop = &dummy;
ListNode* walk = head;
while(walk !=NULL){
if(walk->val == val)
stop->next = walk->next;
else
stop=stop->next;
walk = walk->next;
}
return dummy.next;
}
};
solution2
class Solution {
public:
ListNode* removeElements(ListNode* head, int val) {
ListNode dummy(-1);
dummy.next = head;
ListNode* walk = &dummy;
while(walk->next != NULL){
if(walk->next->val == val)
walk->next = walk->next->next;
else
walk = walk->next;
}
return dummy.next;
}
};