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We're a place where coders share, stay up-to-date and grow their careers. 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);
}