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Rotate Array

medium
Acceptance: 43%
Arrays

Shift every element of an integer array to the right by k positions. Elements that move past the end wrap around to the beginning. The value of k is non-negative and may exceed the array's length.

Examples

Example 1:
Input:arr = [10,20,30,40,50], k = 2
Output:[40,50,10,20,30]
Explanation: After two right rotations, the last two elements wrap to the front.
Example 2:
Input:arr = [5,-3,8], k = 4
Output:[8,5,-3]
Explanation: Since k=4 exceeds the length 3, the effective rotation is 4 mod 3 = 1 step. The last element wraps to the front.

Hints

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

    private void reverse(int[] nums, int start, int end) {
        while (start < end) {
            int temp = nums[start];
            nums[start] = nums[end];
            nums[end] = temp;
            start++;
            end--;
        }
    }
}
Time complexityO(n)
Space complexityO(1)