def merge(L, nL, R, nR, A):
pass
def mergeSort(A, n):
if n <= 1:
return
nL = n//2
nR = n - nL
L = A[:nL]
R = A[nL:n]
mergeSort(L, nL)
mergeSort(R, nR)
merge(L, nL, R, nR, A)
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