Title
Give you the head node head of a linked list, rotate the linked list, and move each node of the linked list k positions to the right.
Example 1:
Input: head = [1,2,3,4,5], k = 2
Output: [4,5,1,2,3]
Example 2:
Input: head = [0,1,2], k = 4
Output: [2,0,1]
prompt:
The number of nodes in the linked list is in the range [0, 500]
-100 <= Node.val <= 100
0 <= k <= 2 * 109
Problem-solving ideas
We turn the singly linked list into a circular linked list, and then just find the breakpoint to disconnect
Code demo
class Solution {
public ListNode rotateRight(ListNode head, int k) {
if(head==null)
return head;
int num=1;
ListNode end=head;
while (end.next!=null)
{
num++;
end=end.next;
}
end.next=head;
int pre=num-k%num;
num=0;
while (num!=pre-1)
{
head=head.next;
num++;
}
ListNode res=head.next;
head.next=null;
return res;
}
}
Effect demonstration
The info
answer was successful:
execution time: 1 ms, defeating 51.22% of Java users
Memory consumption: 37.9 MB, defeating 36.97% of Java users