# 189. Rotate Array

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

**Example 1:**

**Input:**

`[1,2,3,4,5,6,7]`

and

*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:**

`[-1,-100,3,99]`

and

*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]

**Note:**

- 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?

In place rotate

class Solution { /** * @param Integer[] $nums * @param Integer $k * @return NULL */ function rotate(&$nums, $k) { $c = count($nums); $steps = 0; $start = 0; while($steps < $c){ $i = $start; $prev = $nums[$i]; do{ $next = ($i+$k)%$c; $temp = $nums[$next]; $nums[$next] = $prev; $prev = $temp; $i += $k; $i = $i % $c; $steps++; }while($start != $i); $start ++; } } }

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