C++ 程序在排序和旋转的链表中计算旋转

给定一个由 n 个节点组成的链表，该链表首先排序，然后旋转 k 个元素。求 k 的值。

这个想法是遍历单链表来检查当前节点值是否大于下一个节点的值。如果给定条件为真，则中断循环。否则增加计数器变量并通过node->next增加节点。下面是这种方法的实现。

C++

// Program for count number of rotations in
// sorted linked list.
#include 
using namespace std;
/* Linked list node */
struct Node {
    int data;
    struct Node* next;
};
  
// Function that count number of
// rotation in singly linked list.
int countRotation(struct Node* head)
{
    // declare count variable and assign it 1.
    int count = 0;
  
    // declare a min variable and assign to
    // data of head node.
    int min = head->data;
  
    // check that while head not equal to NULL.
    while (head != NULL) {
  
        // if min value is greater then head->data
        // then it breaks the while loop and
        // return the value of count.
        if (min > head->data)
            break;
  
        count++;
  
        // head assign the next value of head.
        head = head->next;
    }
    return count;
}
  
// Function to push element in linked list.
void push(struct Node** head, int data)
{
    // Allocate dynamic memory for newNode.
    struct Node* newNode = new Node;
  
    // Assign the data into newNode.
    newNode->data = data;
  
    // newNode->next assign the address of
    // head node.
    newNode->next = (*head);
  
    // newNode become the headNode.
    (*head) = newNode;
}
  
// Display linked list.
void printList(struct Node* node)
{
    while (node != NULL) {
        printf("%d ", node->data);
        node = node->next;
    }
}
  
// Driver functions
int main()
{
    // Create a node and initialize with NULL
    struct Node* head = NULL;
  
    // push() insert node in linked list.
    // 15 -> 18 -> 5 -> 8 -> 11 -> 12
    push(&head, 12);
    push(&head, 11);
    push(&head, 8);
    push(&head, 5);
    push(&head, 18);
    push(&head, 15);
  
    printList(head);
    cout << endl;
    cout << "Linked list rotated elements: ";
  
    // Function call countRotation()
    cout << countRotation(head) << endl;
  
    return 0;
}

输出

15 18 5 8 11 12 
Linked list rotated elements: 2

有关详细信息，请参阅有关排序和旋转链表中的计数旋转的完整文章！