1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
| class Solution {
public:
ListNode* reverseKGroup(ListNode* head, int k) {
if (head == nullptr || k == 1) {
return head;
}
auto n = head;
ListNode *g = nullptr;
while (n != nullptr) {
ListNode *t = nullptr;
ListNode *h = nullptr;
int i;
for (i = 0; i < k && n != nullptr; i++) {
if (i == 0) {
t = n;
}
auto next = n->next;
n->next = h;
h = n;
n = next;
}
if (n == nullptr && i < k) {
n = h;
h = nullptr;
while (n != nullptr) {
auto next = n->next;
n->next = h;
h = n;
n = next;
}
}
if (g != nullptr) {
g->next = h;
} else {
head = h;
}
g = t;
}
return head;
}
};
|