38 lines
815 B
C++
38 lines
815 B
C++
#include <cstdio>
|
|
|
|
/**
|
|
* Definition for singly-linked list.
|
|
*/
|
|
struct ListNode {
|
|
int val;
|
|
ListNode* next;
|
|
ListNode() : val(0), next(nullptr) {}
|
|
explicit ListNode(int x) : val(x), next(nullptr) {}
|
|
ListNode(int x, ListNode* next) : val(x), next(next) {}
|
|
~ListNode() { delete this->next; }
|
|
};
|
|
|
|
class Solution {
|
|
public:
|
|
static ListNode* middleNode(const ListNode* const head) {
|
|
const auto* fast = head;
|
|
const auto* slow = fast;
|
|
while (fast && fast->next) {
|
|
fast = fast->next->next;
|
|
slow = slow->next;
|
|
}
|
|
return const_cast<ListNode*>(slow);
|
|
}
|
|
};
|
|
|
|
int main() {
|
|
auto* H = new ListNode(1);
|
|
auto* ptr = H;
|
|
for (int i = 2; i <= 6; ++i) {
|
|
ptr->next = new ListNode(i);
|
|
ptr = ptr->next;
|
|
}
|
|
for (const auto* M = Solution::middleNode(H); M; M = M->next)
|
|
std::printf("%d\n", M->val);
|
|
delete H;
|
|
} |