################## selection sort #######################
"" " Select the sort idea is kind of how? Now there is a sequence: alist = [54,226,93,17,77,31,44,55,20] first traversal of all, n is one, the youngest put at the head , alist = [17, 54,226,93,77,31,44,55,20] and the rest of the traverse, n-1 th, to the smallest to the front, alist = [17,20 54,226,93,77 , 31,44,55] and has been circulating, the end, the entire sequence is a small hit, the program to realize the first round, the index of the most minimum value of 0, min = 0, then the traversal, the face it began to do a small exchange, alist [0], alist [ 3] = alist [3], alist [0] the second round, the subscript of the most minimum value of 1, min = 1, then traversing, in case to give it a small began in exchange, alist [1], alist [ 8] = alist [8], alist [0] the third round, the most minimum value of the subscript 2, min = 2, then traverse , the encounter started doing it small exchange, alist [2], alist [ 5] = alist [5], alist [0] so the whole idea is to put the whole sequence is divided into two parts, is always put back go to the front of the smallest, "" "
################## selection sort #######################
# First Edition:
DEF selection_sort (alist):
n-= len (alist)
# n-1 times required for selection operation
for I in Range (n-1):
# minimum recording position
min_index I =
# i + 1 from the position to the end of the selected minimum data
for J in Range (I +. 1, n-):
IF alist [J] <alist [min_index]:
min_index = J
# if the selected data is not in the correct position, exchange
alist [i], alist [ min_index] = alist [min_index], alist [I]
# second Edition:
DEF selection_sort2 (alist):
n-= len (alist)
# n-1 times required for selection operation
for I in Range (n-1):
# record minimum position
min_index = I
# to the end i + 1 selected from the minimum position data
for j in range (i + 1 , n):
IF alist [J] <alist [min_index]:
min_index = J
# if the selected data is not in the correct position, the exchange
IF min_index = I:!
alist [I], alist [min_index] = alist [min_index], alist [I ]
IF the __name__ == '__main__':
alist = [54,226,93,17,77,31,44,55,20]
Print (alist)
selection_sort (alist)
Print (alist)
################## selection sort #######################
################## selection sort #######################
################## selection sort #######################