Arrays: Left Rotation Code Challenge Solved

A left rotation operation on an array shifts each of the array's elements 1 unit to the left. For example, if 2 left rotations are performed on array [1, 2, 3, 4, 5], then the array would become [3, 4, 5, 1, 2].

Given an array a of n integers and a number d, perform d left rotations on the array. Return the updated array to be printed as a single line of space-separated integers.

Function Description
Complete the function rotLeft in the editor below. It should return the resulting array of integers.

rotLeft has the following parameter(s):

• An array of integers a
• An integer d, the number of rotations.

Input Format
The first line contains two space-separated integers n and d, the size of a and the number of left rotations you must perform.
The second line contains n space-separated integers a[i].

Constraints
1 <= n <= 10^5
1 <= d <= n
1 <= a[i] <= 10^6

Output Format
Print a single line of n space-separated integers denoting the final state of the array after performing d left rotations.

Sample Input

4 1 2 3 4 5 

Sample Output

5 1 2 3 4 

Explanation
When we perform left rotations, the array undergoes the following sequence of changes:

[1, 2, 3, 4, 5] [2, 3, 4, 5, 1] [3, 4, 5, 1, 2] [4, 5, 1, 2, 3] [5, 1, 2, 3, 4] 

Solution

function rotLeft($a, $d) { $i = 0; $m = $d; if ($d > sizeof($a)) { $m = ($d % sizeof($a)); } while ($i < $m) { $a[] = $a[$i]; $i++; } array_splice($a, 0, $m); return implode(' ', $a); }