python 返回一个列表中第二小的数的下标

# 返回一个列表中第二大的数

def second(lt):

    max = 0

    s = {}

    for i in range(len(lt)):

        flag = 0

        for j in range(len(lt)):

            if lt[i] <= lt[j] and i != j:

                flag = flag + 1

        s[i] = flag

        if flag > max:

            max = flag

    print(s)

    for i in s:

        if s[i] == max - 1:

            break

    return i



print(second([1,5,7,4,5,6,8,5,9,9,10,11,5,20,19]))