Several common sort algorithm examples in Python implementation _python

Some time ago in preparation for Baidu interview evil supplement things, although the last was brushed, or the days of "booty" put points up, the algorithm has been its own relatively weak place, and later to work harder AH.

Python implements several common sorts, such as fast sorting, sorting, and two-way sorting, and so on.

Copy Code code as follows:

#encoding =utf-8
Import Random
From copy import copy

def directinsertsort (seq):
"" Insert sort Directly "" "
size = Len (seq)
For I in Range (1,size):
TMP, j = seq[i], I
While J > 0 and TMP < SEQ[J-1]:
Seq[j], j = seq[j-1], j-1
SEQ[J] = tmp
return seq

def directselectsort (seq):
"" Select Sort Directly "" "
size = Len (seq)
For I in Range (0,size-1):
K = I;j = i+1
While J < size:
If SEQ[J] < Seq[k]:
K = J
J + 1
SEQ[I],SEQ[K] = Seq[k],seq[i]
return seq

def bubblesort (seq):
"" "Bubble Sort" ""
size = Len (seq)
For I in Range (1,size):
For j in Range (0,size-i):
If seq[j+1] < Seq[j]:
SEQ[J+1],SEQ[J] = seq[j],seq[j+1]
return seq

def _divide (seq, Low, high):
"" "Quick sort partitioning function" "
TMP = Seq[low]
While the low!= is high:
While low < high and Seq[high] >= tmp:high-= 1
If low < high:
Seq[low] = Seq[high]
Low + + 1
While low < high and Seq[low] <= Tmp:low + = 1
If low < high:
Seq[high] = Seq[low]
High-= 1
Seq[low] = tmp
return low

def _quicksort (seq, Low, high):
"" Quick Sort Accessibility function "" "" "
If Low >= High:return
Mid = _divide (seq, low, high)
_quicksort (seq, Low, mid-1)
_quicksort (seq, mid + 1, high)

def quickSort (seq):
"" "Quick sort package Function" "
size = Len (seq)
_quicksort (seq, 0, size-1)
return seq

def merge (seq, left, Mid, right):
TMP = []
I, j = left, mid
While I < mid and J <= right:
If seq[i] < Seq[j]:
Tmp.append (Seq[i])
i + 1
Else
Tmp.append (Seq[j])
J + 1
If I < Mid:tmp.extend (seq[i:])
If J <= Right:tmp.extend (seq[j:])

SEQ[LEFT:RIGHT+1] = tmp[0:right-left+1]

def _mergesort (seq, left, right):
If left = right:
Return
Else
Mid = (left + right)/2
_mergesort (seq, left, mid)
_mergesort (seq, mid + 1, right)
Merge (seq, left, mid+1, right)

#二路并归排序
def mergesort (seq):
size = Len (seq)
_mergesort (seq, 0, size-1)
return seq

if __name__ = = ' __main__ ':
s = [Random.randint (0,100) for I in Range (0,20)]
Print S
print "\ n"
Print Directselectsort (copy (s))
Print Directinsertsort (copy (s))
Print Bubblesort (copy (s))
Print QuickSort (copy (s))
Print mergesort (copy (s))

The results of the operation are as follows:

Copy Code code as follows:

e:\python_project\practice>sorting.py
[10, 47, 56, 76, 64, 84, 26, 8, 47, 51, 88, 81, 32, 95, 91, 29, 28, 69, 61, 45]

[8, 10, 26, 28, 29, 32, 45, 47, 47, 51, 56, 61, 64, 69, 76, 81, 84, 88, 91, 95]
[8, 10, 26, 28, 29, 32, 45, 47, 47, 51, 56, 61, 64, 69, 76, 81, 84, 88, 91, 95]
[8, 10, 26, 28, 29, 32, 45, 47, 47, 51, 56, 61, 64, 69, 76, 81, 84, 88, 91, 95]
[8, 10, 26, 28, 29, 32, 45, 47, 47, 51, 56, 61, 64, 69, 76, 81, 84, 88, 91, 95]
[8, 10, 26, 28, 29, 32, 45, 47, 47, 51, 56, 61, 64, 69, 76, 81, 84, 88, 91, 95]