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:

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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.
/*
 * Code Author: Akshay Miterani
 * DA-IICT
 */
import java.io.*;
import java.math.*;
import java.util.*;

public class Main {

	InputReader in;
	PrintWriter out;
	Main() throws IOException {
		in = new InputReader(System.in);
		out = new PrintWriter(System.out);
		//in = new InputReader(new FileInputStream("input_.txt"));
		//out = new PrintWriter(new File("output_.txt"));
		solve();
		out.close();
	}

	public static void main(String args[]) {
		new Thread(null, new Runnable() {
			public void run() {
				try {
					new Main();
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		}, "1", 1 << 26).start();
	}

	//--------------------My Code Starts Here----------------------
	long mod=(long)1e9+7;
	public void solve() throws IOException{
		int n=in.nextInt();
		long a[]=new long[n];
		for(int i=0;i<n;i++){
			a[i]=in.nextLong();
		}
		long dp[][]=new long[n+1][2];
		for(int i=1;i<n;i++){
			dp[i+1][0]=Math.max(Math.max(dp[i][1]+Math.abs(a[i]-a[i-1]), Math.abs(a[i]-a[i-1])), dp[i+1][0]);
			dp[i+1][1]=Math.max(dp[i][0]-Math.abs(a[i]-a[i-1]), dp[i+1][1]);
		}
		long ans=0;
		for(int i=0;i<=n;i++){
			ans=Math.max(ans, dp[i][0]);
			ans=Math.max(ans, dp[i][1]);
		}
		out.println(ans);
	}
	//---------------------My Code Ends Here-----------------------

	static class Pair implements Comparable<Pair>{
		int x;
		int y;
		Pair(int xx,int yy){
			x=xx;
			y=yy;
		}
		@Override
		public int compareTo(Pair o) {
			if(Long.compare(this.x, o.x)!=0)
				return Long.compare(this.x, o.x);
			else
				return Long.compare(this.y, o.y);
		}
	}
	public static void debug(Object... o) {
		System.out.println(Arrays.deepToString(o));
	}

	static final class InputReader{
		private final InputStream stream;
		private final byte[] buf=new byte[1024];
		private int curChar;
		private int numChars;
		public InputReader(InputStream stream){this.stream=stream;}
		private int read()throws IOException{
			if(curChar>=numChars){
				curChar=0;
				numChars=stream.read(buf);
				if(numChars<=0)
					return -1;
			}
			return buf[curChar++];
		}
		public final int nextInt()throws IOException{return (int)nextLong();}
		public final long nextLong()throws IOException{
			int c=read();
			while(isSpaceChar(c)){
				c=read();
				if(c==-1) throw new IOException();
			}
			boolean negative=false;
			if(c=='-'){
				negative=true;
				c=read();
			}
			long res=0;
			do{
				if(c<'0'||c>'9')throw new InputMismatchException();
				res*=10;
				res+=(c-'0');
				c=read();
			}while(!isSpaceChar(c));
			return negative?(-res):(res);
		}
		public final int[] readIntBrray(int size)throws IOException{
			int[] arr=new int[size];
			for(int i=0;i<size;i++)arr[i]=nextInt();
			return arr;
		}
		public final String next()throws IOException{
			int c=read();
			while(isSpaceChar(c))c=read();
			StringBuilder res=new StringBuilder();
			do{
				res.append((char)c);
				c=read();
			}while(!isSpaceChar(c));
			return res.toString();
		}
		public final String nextLine()throws IOException{
			int c=read();
			while(isSpaceChar(c))c=read();
			StringBuilder res=new StringBuilder();
			do{
				res.append((char)c);
				c=read();
			}while(c!='\n'&&c!=-1);
			return res.toString();
		}
		private boolean isSpaceChar(int c){
			return c==' '||c=='\n'||c=='\r'||c=='\t'||c==-1;
		}
	}
} 