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Java-based LeetCode algorithm problem solutions, regularly updated

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package g0101_0200.s0189_rotate_array;

// #Medium #Top_100_Liked_Questions #Top_Interview_Questions #Array #Math #Two_Pointers
// #Algorithm_I_Day_2_Two_Pointers #Udemy_Arrays #Big_O_Time_O(n)_Space_O(1)
// #2022_06_27_Time_0_ms_(100.00%)_Space_58_MB_(96.22%)

/**
 * 189 - Rotate Array\.
 *
 * Medium
 *
 * Given an array, rotate the array to the right by `k` steps, where `k` is non-negative.
 *
 * **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 <= 10⁵
 * *   -2³¹ <= nums[i] <= 2³¹ - 1
 * *   0 <= k <= 10⁵
 *
 * **Follow up:**
 *
 * *   Try to come up with as many solutions as you can. There are at least **three** different ways to solve this problem.
 * *   Could you do it in-place with `O(1)` extra space?
**/
public class Solution {
    private void reverse(int[] nums, int l, int r) {
        while (l <= r) {
            int temp = nums[l];
            nums[l] = nums[r];
            nums[r] = temp;
            l++;
            r--;
        }
    }

    public void rotate(int[] nums, int k) {
        int n = nums.length;
        int t = n - (k % n);
        reverse(nums, 0, t - 1);
        reverse(nums, t, n - 1);
        reverse(nums, 0, n - 1);
    }
}