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Rotate Array - Array - Medium - LeetCode - MiniTV

Rotate Array - Array - Medium - LeetCode - मिनी टीवी

Given an array, rotate the array to the right by k steps, where k is non-negative.

Follow up:

Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.
Could you do it in-place with O(1) extra space?
 

Example 1:

Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
Example 2:

Input: nums = [-1,-100,3,99], k = 2
Output: [3,99,-1,-100]
Explanation: 
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]
 

Constraints:

1 <= nums.length <= 2 * 104
-231 <= nums[i] <= 231 - 1
0 <= k <= 105

public class Solution {
    public void Rotate(int[] nums, int k) {
        k = k % nums.Length;        
        Reverse(ref nums,0, nums.Length -1 - k);
        Reverse(ref nums, nums.Length-k, nums.Length-1);
        Reverse(ref nums, 0, nums.Length-1);
    }
    
    private void Reverse(ref int[] nums, int start, int end){
        for(int i=start, j=end;i<j;i++,j--){
            Swap(ref nums,i,j);
        }        
    }
    
    private void Swap(ref int[] nums, int source, int destination){
        int temp = nums[source];
        nums[source] = nums[destination];
        nums[destination] = temp;
    }
}

Time Complexity: O(n)

Space Complexity: O(1)