/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc = new Scanner(System.in);
		int n =sc.nextInt();
		int dp[] = new int[n];
		int cost[] = new int[n];
 
		for(int i =0;i<n;i++){
			cost[i] = sc.nextInt();
		}
		dp[0] = 0;
		dp[1] = Math.abs(cost[1] - cost[0]);
		for(int i=2;i<n;i++){
			int ans = Integer.MAX_VALUE;
			ans = Math.min(ans,Math.abs(cost[i]-cost[i-1])+dp[i-1]);
			if(i>=3){
				ans = Math.min(ans,Math.abs(cost[i]-cost[i-3])+dp[i-3]);
			}
			dp[i] =ans;
		}
		System.out.println(dp[n-1]);
	}
}

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Ngo0IDEyIDEzIDE4IDEwIDEy

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