There are N contiguous roads in a line, each road having different height. The i-th road has the height of H[i]. From road i to road i+1, you can do two things:

1, walk to road i+1, which costs |H[i]-H[i+1]|

2, change the height of road i to K, which costs |H[i]-K|

Please calculate the minimum cost of the walk from road 1 to road N.

First line, a number N.(1<=N<=100000)

Second line, N numbers indicating the height of road i.(0<=H[i]<=10000000)

One line, containing a number, the minimum cost.

(please notice the answer maybe huge, equal or larger than 2³¹).

3
3 4 1

3

Change the height of road 2 to 3, and road 3 to 2, cost 2.

Then the H[i] will be 3 3 2, walk from 1 to N cost 1.

The answer is 3.