(一)編寫bsort.py 程式碼如下： bsort.py下載 (484 bytes) | created 11 十一月, 2019
cs = [-1,5,8,1,3]
print ("1:Before bubble sort: cs=",cs)
print ("2: Sorting.........")
for i in range(1,len(cs)-1):
print ("Step i=", i)
for j in range(1,len(cs)-i):
if cs[j] > cs[j+1] :
print (" swap at j=",j, "(",cs[j] ,",",cs[j+1],")")
t=cs[j]
cs[j]=cs[j+1]
cs[j+1]=t
else:
print (" no swap at j=",j, "(",cs[j] ,",",cs[j+1],")")
print (" =>cs=",cs, "j=",j)
print
print ("3:After bubble sort: cs=",cs)
(二)執行結果如下：
1:Before bubble sort: cs= [-1, 5, 8, 1, 3]
2: Sorting.........
Step i= 1
no swap at j= 1 ( 5 , 8 )
=>cs= [-1, 5, 8, 1, 3] j= 1
swap at j= 2 ( 8 , 1 )
=>cs= [-1, 5, 1, 8, 3] j= 2
swap at j= 3 ( 8 , 3 )
=>cs= [-1, 5, 1, 3, 8] j= 3
Step i= 2
swap at j= 1 ( 5 , 1 )
=>cs= [-1, 1, 5, 3, 8] j= 1
swap at j= 2 ( 5 , 3 )
=>cs= [-1, 1, 3, 5, 8] j= 2
Step i= 3
no swap at j= 1 ( 1 , 3 )
=>cs= [-1, 1, 3, 5, 8] j= 1
3:After bubble sort: cs= [-1, 1, 3, 5, 8]
(三)執行結果2如下(修改第一行程式碼為 cs= [-1, 5, 8, 1, 3, 44, 33, 2, 21])：
1:Before bubble sort: cs= [-1, 5, 8, 1, 3, 44, 33, 2, 21]
2: Sorting.........
Step i= 1
no swap at j= 1 ( 5 , 8 )
=>cs= [-1, 5, 8, 1, 3, 44, 33, 2, 21] j= 1
swap at j= 2 ( 8 , 1 )
=>cs= [-1, 5, 1, 8, 3, 44, 33, 2, 21] j= 2
swap at j= 3 ( 8 , 3 )
=>cs= [-1, 5, 1, 3, 8, 44, 33, 2, 21] j= 3
no swap at j= 4 ( 8 , 44 )
=>cs= [-1, 5, 1, 3, 8, 44, 33, 2, 21] j= 4
swap at j= 5 ( 44 , 33 )
=>cs= [-1, 5, 1, 3, 8, 33, 44, 2, 21] j= 5
swap at j= 6 ( 44 , 2 )
=>cs= [-1, 5, 1, 3, 8, 33, 2, 44, 21] j= 6
swap at j= 7 ( 44 , 21 )
=>cs= [-1, 5, 1, 3, 8, 33, 2, 21, 44] j= 7
Step i= 2
swap at j= 1 ( 5 , 1 )
=>cs= [-1, 1, 5, 3, 8, 33, 2, 21, 44] j= 1
swap at j= 2 ( 5 , 3 )
=>cs= [-1, 1, 3, 5, 8, 33, 2, 21, 44] j= 2
no swap at j= 3 ( 5 , 8 )
=>cs= [-1, 1, 3, 5, 8, 33, 2, 21, 44] j= 3
no swap at j= 4 ( 8 , 33 )
=>cs= [-1, 1, 3, 5, 8, 33, 2, 21, 44] j= 4
swap at j= 5 ( 33 , 2 )
=>cs= [-1, 1, 3, 5, 8, 2, 33, 21, 44] j= 5
swap at j= 6 ( 33 , 21 )
=>cs= [-1, 1, 3, 5, 8, 2, 21, 33, 44] j= 6
Step i= 3
no swap at j= 1 ( 1 , 3 )
=>cs= [-1, 1, 3, 5, 8, 2, 21, 33, 44] j= 1
no swap at j= 2 ( 3 , 5 )
=>cs= [-1, 1, 3, 5, 8, 2, 21, 33, 44] j= 2
no swap at j= 3 ( 5 , 8 )
=>cs= [-1, 1, 3, 5, 8, 2, 21, 33, 44] j= 3
swap at j= 4 ( 8 , 2 )
=>cs= [-1, 1, 3, 5, 2, 8, 21, 33, 44] j= 4
no swap at j= 5 ( 8 , 21 )
=>cs= [-1, 1, 3, 5, 2, 8, 21, 33, 44] j= 5
Step i= 4
no swap at j= 1 ( 1 , 3 )
=>cs= [-1, 1, 3, 5, 2, 8, 21, 33, 44] j= 1
no swap at j= 2 ( 3 , 5 )
=>cs= [-1, 1, 3, 5, 2, 8, 21, 33, 44] j= 2
swap at j= 3 ( 5 , 2 )
=>cs= [-1, 1, 3, 2, 5, 8, 21, 33, 44] j= 3
no swap at j= 4 ( 5 , 8 )
=>cs= [-1, 1, 3, 2, 5, 8, 21, 33, 44] j= 4
Step i= 5
no swap at j= 1 ( 1 , 3 )
=>cs= [-1, 1, 3, 2, 5, 8, 21, 33, 44] j= 1
swap at j= 2 ( 3 , 2 )
=>cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44] j= 2
no swap at j= 3 ( 3 , 5 )
=>cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44] j= 3
Step i= 6
no swap at j= 1 ( 1 , 2 )
=>cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44] j= 1
no swap at j= 2 ( 2 , 3 )
=>cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44] j= 2
Step i= 7
no swap at j= 1 ( 1 , 2 )
=>cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44] j= 1
3:After bubble sort: cs= [-1, 1, 2, 3, 5, 8, 21, 33, 44]
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