Assuming: @arr is an array, $n is a number greater than zero and less than the number of elements in the array. Problem: Rotate the array left by $n positions.

Example: 

@arr=(1,2,3,4,5,6,7);
$n=3;
# @arr afterwards:
# (4,5,6,7,1,2,3)

[download]
For the special case $n==1, I think the best solution would be 
push @arr,(shift @arr);

[download]

For the general case, I came up with two possible solutions:

Any ideas about better solutions? ("Better" in the sense of: more compact, or more readable, or faster for large arrays, etc.).

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Rotating an array by rovf

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