python - 插入排序算法不起作用

Question

def insertion_sort(L):
    for i in range(1,len(L)):
        x = i
        while x > 0 and L[x-1] >= L[x]:
            x -= 1
        value = L[i]
        del L[i]
        L.insert(x,value)

a = [5,2,6,3,1,8]

print "Before: ", a
insertion_sort(a)
print "After:  ", a

由于某种原因，列表没有正确排序。我找不到这里的错误。

Answer 1

第四行应该是:

while x > 0 and L[x-1] >= L[i]:

代替

while x > 0 and L[x-1] >= L[x]: