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.
        			/*
        		     * Author- Priyam Vora
        		     * BTech 2nd Year DAIICT
        		     */
     
     
        		    import java.awt.Point;
import java.io.*;
        		    import java.math.*;
        		    import java.util.*;
        		    import javax.print.attribute.SetOfIntegerSyntax;
     
     
     
        		    public class Main{
        		    	private static InputStream stream;
        		    	private static byte[] buf = new byte[1024];
        		    	private static int curChar;
        		    	private static int numChars;
        		    	private static SpaceCharFilter filter;
        		    	private static PrintWriter pw;
        		    	private static long count = 0,mod=1000000007;
        		    //	private static TreeSet<Integer> ts=new TreeSet[200000];
     
        		        public static void main(String[] args) {
        		        	InputReader(System.in);
        		    		pw = new PrintWriter(System.out); 
        		            new Thread(null ,new Runnable(){
        		               public void run(){
        		                   try{
        		                       soln2();
        		                       pw.close();
        		                   } catch(Exception e){
        		                       e.printStackTrace();
        		                   }
        		               }
        		           },"1",1<<26).start();
        		       }

        		    	public static long gcd(long x, long y) {
        		    		if (x == 0)
        		    			return y;
        		    		else
        		    			return gcd( y % x,x);
        		    	}	public static boolean isPrime(int n) {
        		    	// Corner cases
			    		if (n <= 1)
			    			return false;
			    		if (n <= 3)
			    			return true;
			     
			    		// This is checked so that we can skip 
			    		// middle five numbers in below loop
			    		if (n % 2 == 0 || n % 3 == 0)
			    			return false;
			     
			    		for (int i = 5; i * i <= n; i = i + 6)
			    			if (n % i == 0 || n % (i + 2) == 0)
			    				return false;
			     
			    		return true;
			    	}
        		        static LinkedList<Integer> adj[];
        		        static boolean Visited[];
        		        static long color[];
        		        static long dist[][];
        		        static long no_sp_no_sub[];
        		        static long ans=0;

        		        private static void soln2(){
        		        	
        		        	int n=nextInt();
        		        	long a[]=nextLongArray(n);
        		        	long diff[]=new long [n-1];
        		        for(int i=1;i<n;i++){
        		        	diff[i-1]=Math.abs(a[i]-a[i-1]);
        		        }
        		        TreeSet<Long> ts=new TreeSet<Long>();
        		        ts.add((long)0);
        		        long sum=0,max=Long.MIN_VALUE;
        		        for(int i=0;i<n-1;i++){
        		        	if(i%2==0)
        		        		sum+=diff[i];
        		        	else
        		        		sum-=diff[i];
        		        	long lar=ts.last();
        		        	long sma=ts.first();
        		        	max=Math.max(Math.abs(sum-lar), max);
        		        	max=Math.max(max, Math.abs(sum-sma));
        		        	ts.add(sum);
        		        }
        		        pw.println(max);
        		        }
        		    	private static int dfs(int x){
        		    		Visited[x]=true;
        		    		for(int i:adj[x]){
        		    		if(!Visited[i]){
        		    			dfs(i);
        		    		}
        		    		}
        		    		return x;
        		    	}
           		    	private static void buildgraph(int n){
        		    		adj=new LinkedList[n+1];
        		    		Visited=new boolean[n+1];
        		    		color=new long[n+1];
        		    	
        		    		no_sp_no_sub=new long[n+1];
        		    		ans=0;
        		    		Arrays.fill(color, 0);
        		    		for(int i=0;i<=n;i++){
        		    			adj[i]=new LinkedList<Integer>();
        		    		}
     
     
        		    	}
     
        		    	// To Get Input
        		    	// Some Buffer Methods
     
        		    	public static void InputReader(InputStream stream1) {
        		    		stream = stream1;
        		    	}
     
        		    	private static boolean isWhitespace(int c) {
        		    		return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        		    	}
     
        		    	private static boolean isEndOfLine(int c) {
        		    		return c == '\n' || c == '\r' || c == -1;
        		    	}
     
        		    	private static int read() {
        		    		if (numChars == -1)
        		    			throw new InputMismatchException();
        		    		if (curChar >= numChars) {
        		    			curChar = 0;
        		    			try {
        		    				numChars = stream.read(buf);
        		    			} catch (IOException e) {
        		    				throw new InputMismatchException();
        		    			}
        		    			if (numChars <= 0)
        		    				return -1;
        		    		}
        		    		return buf[curChar++];
        		    	}
     
        		    	private static int nextInt() {
        		    		int c = read();
        		    		while (isSpaceChar(c))
        		    			c = read();
        		    		int sgn = 1;
        		    		if (c == '-') {
        		    			sgn = -1;
        		    			c = read();
        		    		}
        		    		int res = 0;
        		    		do {
        		    			if (c < '0' || c > '9')
        		    				throw new InputMismatchException();
        		    			res *= 10;
        		    			res += c - '0';
        		    			c = read();
        		    		} while (!isSpaceChar(c));
        		    		return res * sgn;
        		    	}
     
        		    	private static long nextLong() {
        		    		int c = read();
        		    		while (isSpaceChar(c))
        		    			c = read();
        		    		int sgn = 1;
        		    		if (c == '-') {
        		    			sgn = -1;
        		    			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 res * sgn;
        		    	}
     
        		    	private static String nextToken() {
        		    		int c = read();
        		    		while (isSpaceChar(c))
        		    			c = read();
        		    		StringBuilder res = new StringBuilder();
        		    		do {
        		    			res.appendCodePoint(c);
        		    			c = read();
        		    		} while (!isSpaceChar(c));
        		    		return res.toString();
        		    	}
     
        		    	private static String nextLine() {
        		    		int c = read();
        		    		while (isSpaceChar(c))
        		    			c = read();
        		    		StringBuilder res = new StringBuilder();
        		    		do {
        		    			res.appendCodePoint(c);
        		    			c = read();
        		    		} while (!isEndOfLine(c));
        		    		return res.toString();
        		    	}
     
        		    	private static int[] nextIntArray(int n) {
        		    		int[] arr = new int[n];
        		    		for (int i = 0; i < n; i++) {
        		    			arr[i] = nextInt();
        		    		}
        		    		return arr;
        		    	}
     
        		    	private static int[][] next2dArray(int n, int m) {
        		    		int[][] arr = new int[n][m];
        		    		for (int i = 0; i < n; i++) {
        		    			for (int j = 0; j < m; j++) {
        		    				arr[i][j] = nextInt();
        		    			}
        		    		}
        		    		return arr;
        		    	}
        		    	private static char[][] nextCharArray(int n,int m){
        		    		char [][]c=new char[n][m];
        		    		for(int i=0;i<n;i++){
        		    			String s=nextLine();
        		    			for(int j=0;j<s.length();j++){
        		    				c[i][j]=s.charAt(j);
        		    			}
        		    		}
        		    		return c;
        		    	}
     
        		    	private static long[] nextLongArray(int n) {
        		    		long[] arr = new long[n];
        		    		for (int i = 0; i < n; i++) {
        		    			arr[i] = nextLong();
        		    		}
        		    		return arr;
        		    	}
     
        		    	private static void pArray(int[] arr) {
        		    		for (int i = 0; i < arr.length; i++) {
        		    			pw.print(arr[i] + " ");
        		    		}
        		    		pw.println();
        		    		return;
        		    	}
     
        		    	private static void pArray(long[] arr) {
        		    		for (int i = 0; i < arr.length; i++) {
        		    			pw.print(arr[i] + " ");
        		    		}
        		    		pw.println();
        		    		return;
        		    	}
     
        		    	private static void pArray(boolean[] arr) {
        		    		for (int i = 0; i < arr.length; i++) {
        		    			pw.print(arr[i] + " ");
        		    		}
        		    		pw.println();
        		    		return;
        		    	}
     
        		    	private static boolean isSpaceChar(int c) {
        		    		if (filter != null)
        		    			return filter.isSpaceChar(c);
        		    		return isWhitespace(c);
        		    	}
     
        		    	private interface SpaceCharFilter {
        		    		public boolean isSpaceChar(int ch);
        		    	}
     
     
    }
        		    
        		    class Node{
        		    	int to;
        		    	long dist;
        		    	Node(int to,long dist){
        		    		this.to=to;
        		    		this.dist=dist;
        		    	}
        		    	
        		    }
        			class Pair implements Comparable<Pair>{
						
						int city,pop;
						Pair(int city,int pop){
							this.city=city;
							this.pop=pop;
						}
						@Override
						public int compareTo(Pair o) {
				return pop-this.pop;
				
						}
						public int hashCode() {
		    	    			int hu = (int) (city ^ (city >>> 32));
		    	    			int hv = (int) (pop ^ (pop >>> 32));
		    	    			//int hw = (int) (mass ^ (mass >>> 32));
		    	    			return 31 * hu + hv ;
		    	    		//return 0;
		    				}
		    				public boolean equals(Object o) {
		    	    			Pair other = (Pair) o;
		    	    			return city == other.city && pop == other.pop;
		    	    		}
					}  class Dsu{
	    		    	private int rank[], parent[] ,n;
	    		    	private static int[] parent1;
	    		    	Dsu(int size){
	    		    		this.n=size+1;
	    		    		rank=new int[n];
	    		    		//parent=new int[n];
	    		    		parent=new int[n];
	    		    	makeSet();
	    		
	    		    	}
	    		    	
	    		    	void makeSet(){
	    		    		for(int i=0;i<n;i++){
	    		    			parent[i]=i;
	    		    		}
	    		    	}
	    		    	
	    		    	int find(int x){
	    		    		if(parent[x]!=x){
	    		    			
	    		    			parent[x]=find(parent[x]);
	    		    		}
	    		    		return parent[x];
	    		    	}
	    		    
	    		    	
	    		    	boolean union(int x,int y){
	    		    		int xRoot=find(x);
	    		    		int yRoot=find(y);
	    		    		
	    		    		if(xRoot==yRoot)
	    		    			return false;
	    		    		if(rank[xRoot]<rank[yRoot]){
	    		    		parent[xRoot]=yRoot;	
	    		    		}else if(rank[yRoot]<rank[xRoot]){
	    		    			parent[yRoot]=xRoot;
	    		    		}else{
	    		    			parent[yRoot]=xRoot;
	    		    			rank[xRoot]++;
	    		    		}
	    		    		return true;
	    		    	}

	    		     
	    		    }