import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}
void readA(T)(size_t n,ref T[]t){t=new T[](n);auto r=rdsp;foreach(ref v;t)pick(r,v);}

void main()
{
  int n; readV(n);
  int[] h; readA(n, h);

  auto dp = new int[](n);
  dp[0] = 0; dp[1] = (h[1]-h[0]).abs;
  foreach (i; 2..n)
    dp[i] = min(dp[i-1] + (h[i]-h[i-1]).abs, dp[i-2] + (h[i]-h[i-2]).abs);

  writeln(dp[$-1]);
}
