Python Solution For HackerRank Problem: Arrays: Left Rotation

Solving a simple HackerRank problem called: Arrays: Left Rotation using Python.

Problem

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.

See the full description of the problem here : Arrays: Left Rotation

Solution

This is the logic.
If a = 5, d = 4
1 2 3 4 5
Here 
alist[d:] = 5
alist[:d] = 1 2 3 4
so  alist[d:]+alist[:d] = 5 1 2 3 4 

Sample Input

5 4
1 2 3 4 5

Sample Output

5 1 2 3 4

Let me know if you got any better solution.