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Rotate Array to the Right by K StepsWrite a C++ function to rotate an array to the right by K steps.The function should handle negative values of K by rotating to the left. Optimize for time complexity.Constraints:NAExample:Sample Input:71 2 3 4 5 6 73Sample Output:4 5 6 7 1 2 3 Explanation:Input:7------------>Size of array1 2 3 4 5 6 7 --->Elements of array3  ---->Steps to be rotated before reversalOutput:After rotating array by 3 steps, reverse the remaining elements in the arrays.

Question

Rotate Array to the Right by K StepsWrite a C++ function to rotate an array to the right by K steps.The function should handle negative values of K by rotating to the left. Optimize for time complexity.Constraints:NAExample:Sample Input:71 2 3 4 5 6 73Sample Output:4 5 6 7 1 2 3 Explanation:Input:7------------>Size of array1 2 3 4 5 6 7 --->Elements of array3  ---->Steps to be rotated before reversalOutput:After rotating array by 3 steps, reverse the remaining elements in the arrays.

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Solution

Here is a C++ function that rotates an array to the right by K steps. This function handles negative values of K by rotating to the left. The function uses the reverse algorithm to optimize for time complexity.

#include <algorithm>
#include <vector>

void rotate(std::vector<int>& nums, int k) {
    k = k % nums.size(); // Handle the case when k is larger than the size of the array
    if (k < 0) { // Handle the case when k is negative
        k += nums.size();
    }
    std::reverse(nums.begin(), nums.end()); // Reverse the whole array
    std::reverse(nums.begin(), nums.begin() + k); // Reverse the first part
    std::reverse(nums.begin() + k, nums.end()); // Reverse the second part
}

Here is how it works:

  1. If k is larger than the size of the array, we only need to rotate k % nums.size() steps.
  2. If k is negative, we convert it to a positive number by adding the size of the array.
  3. We reverse the whole array.
  4. We reverse the first k elements.
  5. We reverse the remaining elements.

For example, if the input array is [1, 2, 3, 4, 5, 6, 7] and k is 3, the output will be [5, 6, 7, 1, 2, 3, 4].

This problem has been solved

Similar Questions

To rotate an array to the right by K positions, you would:

RotationGiven an array Arr[] of N integers and a positive integer K. The task is to cyclically rotate the arrayclockwise by K.Note: Keep the first position of the array unaltered.Constraints:Constraints1 < N <=100-100 <= Arr[i] <=1001 <=K <=100Input format for testingThe candidate should write the code to accept the inputs separated by a new line.First Input: Accept a single positive integer value for N representing the size of Arr[]Second Input: Accept N number of integer values separated by a new line, as elements of Arr[]Third input: Accept a single positive integer value for K representing the number of rotations.Output format for testingThe output must be N integer numbers separated by a single space character.Additional messages in the output will result in the failure of test cases.Example:Input5 -- Value of N{10, 20, 30, 40, 50} -- Elements ofArr[]2 -- Value of KOutput40 50 10 20 30Explanation:Arr[] = {10, 20, 30, 40, 50} and K = 2 (Two cyclical rotations)After 1st rotation = {10, 50, 20, 30, 40}After 2nd rotation = {10, 40, 50, 20, 30}

A left rotation operation on an array of size shifts each of the array's elements unit to the left. Given an integer, , rotate the array that many steps left and return the result.ExampleAfter rotations, .Function DescriptionComplete the rotateLeft function in the editor below.rotateLeft has the following parameters:int d: the amount to rotate byint arr[n]: the array to rotateReturnsint[n]: the rotated arrayInput FormatThe first line contains two space-separated integers that denote , the number of integers, and , the number of left rotations to perform.The second line contains space-separated integers that describe .ConstraintsSample Input5 41 2 3 4 5Sample Output5 1 2 3 4ExplanationTo perform left rotations, the array undergoes the following sequence of changes:

Rotate an ArrayA group of students is working on a robotics project where a sensor array needs to be adjusted to avoid obstacles. They need a function to simulate rotating the sensor readings (an array of integers) to the right by a given number of positions.Write a function that rotates an array of integers to the right by a given number of positions.Constraints:NAExample:Input:51 2 3 4 51Output:5 1 2 3 4Explanation:Input:5  --->size of array1 2 3 4 5----->elements in array1 ---> number of shifts to be doneOutput:5 1 2 3 4  ---> array after rotating it by 1 step

Given an array Arr[] of N integers and a positive integer K. The task is to cyclically rotate the arrayclockwise by K.Note: Keep the first position of the array unaltered.

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