Middle Of The Linked List Problem
Description
LeetCode Problem 876.
Given the head of a singly linked list, return the middle node of the linked list. If there are two middle nodes, return the second middle node.
Example 1:
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Input: head = [1,2,3,4,5]
Output: [3,4,5]
Explanation: The middle node of the list is node 3.
Example 2:
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Input: head = [1,2,3,4,5,6]
Output: [4,5,6]
Explanation: Since the list has two middle nodes with values 3 and 4, we return the second one.
Constraints:
- The number of nodes in the list is in the range [1, 100].
- 1 <= Node.val <= 100
Sample C++ Code
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/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode() : val(0), next(nullptr) {}
* ListNode(int x) : val(x), next(nullptr) {}
* ListNode(int x, ListNode *next) : val(x), next(next) {}
* };
*/
class Solution {
public:
ListNode* middleNode(ListNode* head) {
ListNode* currNode;
ListNode* midNode;
currNode = head;
midNode = head;
int cnt = 1;
while (currNode != NULL) {
if (cnt % 2 == 0)
midNode = midNode->next;
currNode = currNode->next;
cnt ++;
}
return midNode;
}
};