rotate left algorithm - NormandaleWells/CSn GitHub Wiki
rotate_left(A)
rotate_left rotates the entire array A one position to the left. That is, A[1] is copied to A[0], A[2] is copied to A[1], etc. A[0] is copied to A[A.length-1].
rotate_left(A)
if A.length <= 1
return
A.type t = A[0]
for (index i = 1; i < A.length; i++)
A[i-1] = A[i]
A[A.length-1] = t