def shell(a): n=len(a)//2 while n>0: for i in range(n,len(a)): key=a[i] k=i while k>=n and a[k-n]>key: a[k]=a[k-n] k=k-n a[k]=key n=n//2 a=[12, 34, 54, 2, 3] result=shell(a) print(a)