def selection_sort(): L [96, 2, 65, 23, 47, 58, 8, 48, 69, 92, 34, 83, 93, 47, 45, 55, 95, 15, 92, 24, 64, 19, 29, 55, 35, 48, 39, 29, 63, 94, 99, 38, 50, 10, 10, 93, 74, 27, 74, 44, 29, 81, 85, 86, 74, 30, 50, 50, 12, 12, 38, 75, 41, 87, 80, 97, 16, 48, 65, 69, 83, 71, 28, 9, 64, 69, 27, 74, 74, 86, 40, 69, 79, 79, 77, 100, 53, 72, 77, 16, 8, 36, 41, 58, 59, 29, 46, 79, 81, 66, 8, 35, 60, 52, 2, 82, 2, 36, 79, 66] n len(L) for i in range(n - 1): min_index i for j in range(i 1, n): if L[j] L[min_index]: min_index j if min_index ! i: L[i], L[min_index] L[min_index], L[i] return L
def selection_sort2(): L [96, 2, 65, 23, 47, 58, 8, 48, 69, 92, 34, 83, 93, 47, 45, 55, 95, 15, 92, 24, 64, 19, 29, 55, 35, 48, 39, 29, 63, 94, 99, 38, 50, 10, 10, 93, 74, 27, 74, 44, 29, 81, 85, 86, 74, 30, 50, 50, 12, 12, 38, 75, 41, 87, 80, 97, 16, 48, 65, 69, 83, 71, 28, 9, 64, 69, 27, 74, 74, 86, 40, 69, 79, 79, 77, 100, 53, 72, 77, 16, 8, 36, 41, 58, 59, 29, 46, 79, 81, 66, 8, 35, 60, 52, 2, 82, 2, 36, 79, 66] n len(L) for i in range(n): flag False for j in range(n - i - 1): if L[j] L[j 1]: L[j], L[j 1] L[j 1], L[j] flag True if not flag: break return L
print( Selection sort function1 run 1000 times, cost: , timeit.repeat(stmt selection_sort() , setup from __main__ import selection_sort , repeat 2, number 1000), seconds. ) print( Selection sort function2 run 1000 times, cost: , timeit.repeat(stmt selection_sort2() , setup from __main__ import selection_sort2 , repeat 2, number 1000), seconds. )
性能显而易见 前者要比后者高一倍
