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psf/black code formatting (#1421)

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* added sol3.py for problem_20

* added sol4.py for problem_06

* ran `black .` on `\Python`
This commit is contained in:
Ankur Chattopadhyay
2019-10-22 22:43:48 +05:30
committed by Christian Clauss
parent 11e2207182
commit 7592cba417
28 changed files with 413 additions and 252 deletions
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67
divide_and_conquer/mergesort.py
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@@ -1,45 +1,48 @@
def merge(a,b,m,e):
l=a[b:m+1]
r=a[m+1:e+1]
k=b
i=0
j=0
while i<len(l) and j<len(r):
#change sign for Descending order
if l[i]<r[j]:
a[k]=l[i]
i+=1
def merge(a, b, m, e):
l = a[b : m + 1]
r = a[m + 1 : e + 1]
k = b
i = 0
j = 0
while i < len(l) and j < len(r):
# change sign for Descending order
if l[i] < r[j]:
a[k] = l[i]
i += 1
else:
a[k]=r[j]
j+=1
k+=1
while i<len(l):
a[k]=l[i]
i+=1
k+=1
while j<len(r):
a[k]=r[j]
j+=1
k+=1
a[k] = r[j]
j += 1
k += 1
while i < len(l):
a[k] = l[i]
i += 1
k += 1
while j < len(r):
a[k] = r[j]
j += 1
k += 1
return a
def mergesort(a,b,e):
def mergesort(a, b, e):
"""
>>> mergesort([3,2,1],0,2)
[1, 2, 3]
>>> mergesort([3,2,1,0,1,2,3,5,4],0,8)
[0, 1, 1, 2, 2, 3, 3, 4, 5]
"""
if b<e:
m = (b+e)//2
#print("ms1",a,b,m)
mergesort(a,b,m)
#print("ms2",a,m+1,e)
mergesort(a,m+1,e)
#print("m",a,b,m,e)
merge(a,b,m,e)
if b < e:
m = (b + e) // 2
# print("ms1",a,b,m)
mergesort(a, b, m)
# print("ms2",a,m+1,e)
mergesort(a, m + 1, e)
# print("m",a,b,m,e)
merge(a, b, m, e)
return a
if __name__ == "__main__":
import doctest
doctest.testmod()