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MS
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MS
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import sys
def main(args):
file = str(args[1])
with open(file) as f:
N = int(f.readline())
A = list(map(int,f.readline().split()))
merge_sort(A,0,N-1)
with open('rosalind_ms_res.txt','w') as f:
f.write(' '.join(map(str,A)))
def merge(arr,l,m,r):
n1 = m-l+1
n2 = r-m
L = [0]*(n1)
R = [0]*(n2)
for i in range(n1):
L[i] = arr[i+l]
for i in range(n2):
R[i] = arr[m+i+1]
i = 0 # Initial index of first subarray
j = 0 # Initial index of second subarray
k = l # Initial index of merged subarray
while i < n1 and j < n2:
if L[i] <= R[j]:
arr[k] = L[i]
i += 1
else:
arr[k] = R[j]
j += 1
k += 1
while i < n1:
arr[k] = L[i]
i += 1
k += 1
while j < n2:
arr[k] = R[j]
j += 1
k += 1
def merge_sort(arr,l,r):
if l < r:
m = (l+r-1)//2
merge_sort(arr,l,m)
merge_sort(arr,m+1,r)
merge(arr,l,m,r)
if '__main()__':
main(sys.argv)