C++ Program for Generating Lyndon words of length n

C++ Program for Reversal algorithm for right rotation of an array

Last Updated : 30 Mar, 2022

Given an array, right rotate it by k elements.

After K=3 rotation

Examples:

Input: arr[] = {1, 2, 3, 4, 5, 
                6, 7, 8, 9, 10}
          k = 3
Output: 8 9 10 1 2 3 4 5 6 7

Input: arr[] = {121, 232, 33, 43 ,5}
           k = 2
Output: 43 5 121 232 33

Note : In the below solution, k is assumed to be smaller than or equal to n. We can easily modify the solutions to handle larger k values by doing k = k % n
Algorithm:

rotate(arr[], d, n)
  reverseArray(arr[], 0, n-1) ;
  reverse(arr[], 0, d-1);
  reverse(arr[], d, n-1);

Below is the implementation of above approach:

C++

// C++ program for right rotation of 
// an array (Reversal Algorithm)
#include <bits/stdc++.h>
 
/*Function to reverse arr[] 
from index start to end*/
void reverseArray(int arr[], int start,
                            int end)
{
    while (start < end)
    {
        std::swap(arr[start], arr[end]);
        start++;
        end--;
    }
}
 
/* Function to right rotate arr[]
of size n by d */
void rightRotate(int arr[], int d, int n)
{
    reverseArray(arr, 0, n-1);
    reverseArray(arr, 0, d-1);
    reverseArray(arr, d, n-1);
}
 
/* function to print an array */
void printArray(int arr[], int size)
{
    for (int i = 0; i < size; i++)
        std::cout << arr[i] << " ";
}
 
// driver code
int main()
{
    int arr[] = {1, 2, 3, 4, 5, 
                6, 7, 8, 9, 10};
     
    int n = sizeof(arr)/sizeof(arr[0]);
    int k = 3;
     
    rightRotate(arr, k, n);
    printArray(arr, n);
 
    return 0;
} 

Output:

8 9 10 1 2 3 4 5 6 7

Time Complexity: O(N)

Auxiliary Space: O(1)

Please refer complete article on Reversal algorithm for right rotation of an array for more details!

C++ Program for Generating Lyndon words of length n

kartik

Improve

Article Tags :

Practice Tags :

Similar Reads

C++ Program for Reversal algorithm for array rotation

Write a function rotate(arr[], d, n) that rotates arr[] of size n by d elements. Example : Input : arr[] = [1, 2, 3, 4, 5, 6, 7] d = 2 Output : arr[] = [3, 4, 5, 6, 7, 1, 2] Rotation of the above array by 2 will make array Recommended: Please solve it on â€œPRACTICE â€ first, before moving on to the so

C++ Program for Block swap algorithm for array rotation

Write a function rotate(ar[], d, n) that rotates arr[] of size n by d elements. Rotation of the above array by 2 will make array Algorithm : Initialize A = arr[0..d-1] and B = arr[d..n-1] 1) Do following until size of A is equal to size of B a) If A is shorter, divide B into Bl and Br such that Br i

C++ Program to Find Mth element after K Right Rotations of an Array

Given non-negative integers K, M, and an array arr[ ] consisting of N elements, the task is to find the Mth element of the array after K right rotations. Examples: Input: arr[] = {3, 4, 5, 23}, K = 2, M = 1 Output: 5 Explanation: The array after first right rotation a1[ ] = {23, 3, 4, 5} The array a

C++ Program for Left Rotation and Right Rotation of a String

Given a string of size n, write functions to perform the following operations on a string- Left (Or anticlockwise) rotate the given string by d elements (where d <= n)Right (Or clockwise) rotate the given string by d elements (where d <= n). Examples: Input : s = "GeeksforGeeks" d = 2 Output :

C++ Program to Find Range sum queries for anticlockwise rotations of Array by K indices

Given an array arr consisting of N elements and Q queries of the following two types: 1 K: For this type of query, the array needs to be rotated by K indices anticlockwise from its current state.2 L R: For this query, the sum of the array elements present in the indices [L, R] needs to be calculated

C++ Program for Check if an array is sorted and rotated

Given an array of N distinct integers. The task is to write a program to check if this array is sorted and rotated counter-clockwise. A sorted array is not considered as sorted and rotated, i.e., there should at least one rotation.Examples: Input : arr[] = { 3, 4, 5, 1, 2 } Output : YES The above ar

All reverse permutations of an array using STL in C++

Given an array, the task is to print or display all the reverse permutations of this array using STL in C++. Reverse permutation means, for an array {1, 2, 3}: forward permutations: 1 2 3 1 3 2 2 1 3 2 3 1 3 1 2 3 2 1 reverse permutations: 3 2 1 3 1 2 2 3 1 2 1 3 1 3 2 1 2 3 Examples: Input: a[] = {

C++ Program to Print array after it is right rotated K times

Given an Array of size N and a values K, around which we need to right rotate the array. How to quickly print the right rotated array?Examples :Â Â Input: Array[] = {1, 3, 5, 7, 9}, K = 2. Output: 7 9 1 3 5 Explanation: After 1st rotation - {9, 1, 3, 5, 7} After 2nd rotation - {7, 9, 1, 3, 5} Input:

C++ Program for Search an element in a sorted and rotated array

An element in a sorted array can be found in O(log n) time via binary search. But suppose we rotate an ascending order sorted array at some pivot unknown to you beforehand. So for instance, 1 2 3 4 5 might become 3 4 5 1 2. Devise a way to find an element in the rotated array in O(log n) time.Â Exam

C++ Program to Copy the Contents of One Array Into Another in the Reverse Order

Given an array, the task is to copy these array elements into another array in reverse array.Examples: Input: array: 1 2 3 4 5 Output: 5 4 3 2 1 Input: array: 10 20 30 40 50 Output: 50 40 30 20 10 Let len be the length of original array. We copy every element original_arr[i] to copy_arr[n-i-1] to ge