1. (2021高一上·期中) 下列程序执行后的结果为（　　）  

L = [1,-2,3,7,-8,-9,10]

j=len(L)-1

i = 0

k = 0

while i<j:

    while L[i]>0:

        i=i+1

    while L[j]<0:

        j=j-1

    if i<j:

        k = L[i]

        L[i]=L[j]

        L[j] = k

print(L)