Something happened in Uzhlyandia again... There are riots on the streets... Famous Uzhlyandian superheroes Shean the Sheep and Stas the Giraffe were called in order to save the situation. Upon the arriving, they found that citizens are worried about maximum values of the Main Uzhlyandian Function f, which is defined as follows:

<image>

In the above formula, 1 ≤ l < r ≤ n must hold, where n is the size of the Main Uzhlyandian Array a, and |x| means absolute value of x. But the heroes skipped their math lessons in school, so they asked you for help. Help them calculate the maximum value of f among all possible values of l and r for the given array a.

Input

The first line contains single integer n (2 ≤ n ≤ 105) — the size of the array a.

The second line contains n integers a1, a2, ..., an (-109 ≤ ai ≤ 109) — the array elements.

Output

Print the only integer — the maximum value of f.

Examples

Input

5
1 4 2 3 1


Output

3

Input

4
1 5 4 7


Output

6

Note

In the first sample case, the optimal value of f is reached on intervals [1, 2] and [2, 5].

In the second case maximal value of f is reachable only on the whole array.
//package com.company;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
public class Main {

    public static void main(String[] args) throws IOException {
        // write your code here
       Scanner s = new Scanner(System.in);
         // BufferedReader s=new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb = new StringBuilder();
      int n=s.nextInt();Long[] a=new Long[n];
      for(int i=0;i<n;i++){
          a[i]=s.nextLong();
      }max=Long.MIN_VALUE;Long[] []dp=new Long[n][2];
        for(int i=0;i<n-1;i++){
          if(i==0){
              dp[i][1]=Math.abs(a[i]-a[i+1]);dp[i][0]=0L;
          }else{
              dp[i][1]=dp[i-1][0]+Math.abs(a[i]-a[i+1]);
              dp[i][0]=Math.max(0,dp[i-1][1]-Math.abs(a[i]-a[i+1]));
          }max=Math.max(max,dp[i][1]);
        }
        System.out.println(max);
    }



    static double power(double x, long y, int p)
    {
        double res = 1;
 x = x % p;
        while (y > 0)
        {
            if((y & 1)==1)
                res = (res * x) % p;
            y = y >> 1;
            x = (x * x) % p;
        }
        return res;
    }
    static int m;
    static int n;
    static int path = Integer.MAX_VALUE;
    static int got = 0;
static Long[] sum;static Long[] a;
    public static long dfs(int i, ArrayList<Integer>[] h, int[] vis) {
        vis[i] = 1;
        sum[i]+=a[i];if(h[i]==null) return sum[i];
        for (Integer j : h[i]) {
            if (vis[j] == 0) {
                sum[i]+=dfs(j, h, vis);
            }
        }return sum[i];
    }static long max=Long.MIN_VALUE;static long max1=Long.MIN_VALUE;
    public static void dfs1(int i, ArrayList<Integer>[] h, int[] vis) {
        vis[i] = 1;//sum[i]+=a[i];
        if(h[i]==null) return ;
        for (Integer j : h[i]) {
            if (vis[ j] == 0) {
                if(sum[j]>max) {max1=max;max=sum[j];}
                else if(sum[j]>max1) max1=sum[j];
                dfs1(j, h, vis);
            }
        }return ;
    }static long fans=Long.MIN_VALUE;
    public static long dfs2(int i, ArrayList<Integer>[] h, int[] vis) {
        long max2=Long.MIN_VALUE;long max3=Long.MIN_VALUE;
        vis[i] = 1;if(h[i]==null) return a[i];
        for (Integer j : h[i]) {
            if (vis[ j] == 0) {
              long k=  dfs2(j, h, vis);
              if(k>max2) { max3=max2;max2=k;}
              else if(k>max3) max3=k;
            }
        }
     //   System.out.println(i+" "+max2+" "+max3+" "+sum[i]);
        if(max2!=Long.MIN_VALUE&&max3!=Long.MIN_VALUE&&max2+max3> fans) fans=max2+max3;
     //   if(i==1) return max2;
        return Math.max(sum[i],max2);
    }

    public static void bfs(int i, HashMap<Integer, Integer>[] h, int[] vis, int len, int papa) {
        Queue<Integer> q = new LinkedList<Integer>();
        q.add(i);

    }


    static int i(String a){
        return Integer.parseInt(a);
    }static long l(String a){
        return Long.parseLong(a);
    }static String[] inp() throws IOException{
        BufferedReader s=new BufferedReader(new InputStreamReader(System.in));
        return s.readLine().trim().split("\\s+");
    }
}

class Student
{
 int t,l,r;
//    String name, address;

    // Constructor
    public Student(int t,int r)
    {this.t=t;

        this.r=r;
    }

    // Used to print student details in main()
    public String toString()
    {
        return this.t + " " +this.l+" "+this.r;
    }
}

class Sortbyroll implements Comparator<Student>
{
    // Used for sorting in ascending order of
    // roll number
    public int compare(Student a, Student b)
    {
        return a.t-b.t;
    }
}