# HackerRank ‘Left Rotation’ Solution

H
##### Short Problem Definition:

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].

Arrays: Left Rotation

##### Complexity:

time complexity is O(N)

space complexity is O(N)

##### Execution:

Solutions like this is where python really shines. Simple and straight forward.

##### Solution:
 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 `#!/bin/python`   `import` `math` `import` `os` `import` `random` `import` `re` `import` `sys`   `# Complete the rotLeft function below.` `def` `rotLeft(a, d):` `    ``return` `a[d:] ``+` `a[:d]`   `if` `__name__ ``=``=` `'__main__'``:` `    ``fptr ``=` `open``(os.environ[``'OUTPUT_PATH'``], ``'w'``)`   `    ``nd ``=` `raw_input``().split()`   `    ``n ``=` `int``(nd[``0``])`   `    ``d ``=` `int``(nd[``1``])`   `    ``a ``=` `map``(``int``, ``raw_input``().rstrip().split())`   `    ``result ``=` `rotLeft(a, d)`   `    ``fptr.write(``' '``.join(``map``(``str``, result)))` `    ``fptr.write(``'n'``)`   `    ``fptr.close()`