import random
lis=
list
(range
(100))
random.
shuffle
(lis)
print
(lis)
def bubblesort
(arr)
:for i in
range(1
,len
(arr)):
for j in
range(0
,len
(arr)
-i):
if arr[j]
>arr[j+1]
: arr[j]
,arr[j+1]
=arr[j+1]
,arr[j]
return arr
print
(bubblesort
(lis)
)
def selectionsort
(arr)
:for i in
range
(len
(arr)):
temp=i
for j in
range
(i,len
(arr)-1
):if arr[temp]
>arr[j]
: temp=j
arr[i]
,arr[temp]
=arr[temp]
,arr[i]
return arr
print
(selectionsort
(lis)
)
def insertionsort
(arr)
:for i in
range(1
,len
(arr)):
for j in
range(0
,i):
if arr[i]
:for k in
range
(j,i)
: arr[k]
,arr[i]
=arr[i]
,arr[k]
return arr
print
(insertionsort
(lis)
)
import math
def shellsort
(arr)
: gap=
1while
(gap <
len(arr)/3
):gap = gap*3+
1while gap >0:
for i in
range
(gap,
len(arr)):
temp = arr[i]
j = i-gap
while j >=
0 and arr[j]
> temp:
arr[j+gap]
=arr[j]
j-=gap
arr[j+gap]
= temp
gap = math.
floor
(gap/3)
return arr
print
(shellsort
(lis)
)
#遞迴
def mergesort
(arr)
: n =
len(arr)
if n <=1:
return arr
n = n//2
sub1 =
mergesort
(arr[
:n])
sub2 =
mergesort
(arr[n:])
return
merge
(sub1, sub2)
#合併兩個有序陣列
def merge
(sub1, sub2)
: n1 =
len(sub1)
n2 =
len(sub2)
i =0 j =
0 merge =
while i < n1 and j < n2:
if sub1[i]
< sub2[j]
: merge.
(sub1[i]
) i +=
1else
: merge.
(sub2[j]
) j +=
1 # 沒複製完的
while i < n1:
merge.
(sub1[i]
) i +=
1while j < n2:
merge.
(sub2[j]
) j +=
1return merge
print
(mergesort
(lis)
)
def mergesort
(arr)
: n =
len(arr)
size =
1 # 表示每一步要歸併的陣列的長度
m =while size <= n:
for i in
range(0
, n-size, size+size)
: m =
merge
(arr[i: i+size]
, arr[i+size:
min(i+size+size, n)
]) # min
(i+size+size, n)為了最後一組陣列可能不夠全
arr[i:
min(i+size+size, n)
]= m[
:] # 把merge得到的結果賦值給原始陣列
size += size # 陣列長度每次乘二
return m
#合併兩個有序陣列
def merge
(sub1, sub2)
: n1 =
len(sub1)
n2 =
len(sub2)
i =0 j =
0 merge =
while i < n1 and j < n2:
if sub1[i]
< sub2[j]
: merge.
(sub1[i]
) i +=
1else
: merge.
(sub2[j]
) j +=
1 # 沒複製完的
while i < n1:
merge.
(sub1[i]
) i +=
1while j < n2:
merge.
(sub2[j]
) j +=
1return merge
print
(mergesort
(lis)
)
def quicksort
(arr)
:return
helpqs
(arr,0,
len(arr)-1
)def helpqs
(arr,left,right)
:if left>right:
return
k=arr[left]
i=left
j=right
while i!=j:
while arr[j]
>k and ij-=
1while arr[i]
<=k and ii+=
1if iarr[i]
,arr[j]
=arr[j]
,arr[i]
arr[left]
,arr[i]
=arr[i]
,arr[left]
helpqs
(arr,left,i-1)
helpqs
(arr,i+
1,right)
return arr
print
(quicksort
(lis)
)
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