Write a function named rotate
that accepts a reference to a pointer to a ListNode
representing the front of a linked list.
Your function should move the value at the front of a list of integers to the end of the list.
For example, suppose a variable named front
points to the front of a list containing the following sequence of values:
{8, 23, 19, 7, 45, 98, 102, 4}
The call of rotate(front);
should move the value 8 from the front of the list to the back, yielding this sequence of values:
{23, 19, 7, 45, 98, 102, 4, 8}
The other values in the list should retain the same order as in the original list.
If the function is called for a list of 0 or 1 elements it should have no effect on the list.
Constraints:
Do not modify the data
field of existing nodes; change the list by changing pointers only.
Do not construct any new ListNode
objects in solving this problem (though you may create as many ListNode*
pointer variables as you like).
Do not use any auxiliary data structures to solve this problem (no array, vector, stack, queue, string, etc).
Assume that you are using the ListNode
structure as defined below:
struct ListNode {
int data; // value stored in each node
ListNode* next; // pointer to next node in list (nullptr if none)
}