How to find second largest number in a list?

Question

So I have to find the second largest number from list. I am doing it through simple loops.

My approach is to divide a list into two parts and then find the largest n

Answer 1

Here is my program, irrespective of complexity

if __name__ == '__main__':
    alist=[-45,0,3,10,90,5,-2,4,18,45,100,1,-266,706]
    alist1 = [ ]
    [alist1.append(x) for x in alist if x not in alist1]
    alist1.sort()
    print alist1[-2]