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.
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[]) throws Exception {
		InputReader(System.in);
		pw = new PrintWriter(System.out); 
        new Thread(null ,new Runnable(){
           public void run(){
               try{
                   soln();
                   pw.close();
               } catch(Exception e){
                   e.printStackTrace();
               }
           }
       },"1",1<<26).start();
	}
	//----------------------------------------My Code------------------------------------------------//
	public static class Participant implements Comparable<Participant>{
		String name;
		int score;
		Participant(String s, int n){
			this.name=s;
			this.score=n;
		}
		@Override
		public int compareTo(Participant o){
			if(o.score<score){
				return 1;
			}
			else if(o.name.equals(this.name)) return 0;
			else{
				return -1;
			}
		}
		@Override
		public boolean equals(Object obj){
			if(obj==null) return false;
			if(obj.getClass()!=this.getClass()) return false;
			Participant prt=(Participant) obj;
			if(this.name.equals(prt.name)) return true;
			return false;
		}
		@Override
		public int hashCode(){
			return this.name.hashCode();
		}
	}
	public static class Comp<T> implements Comparator<Participant>{
		@Override
		public int compare(Participant p1, Participant p2) {	
			if(p1.score<p2.score) return 1;
			else
			return 0;
		}
	}
	private static void soln() {
		int n=nextInt();
		int[] arr=nextIntArray(n);
		long[] dp=new long[n-1];
		int current=1;
		dp[0]=Math.abs(arr[0]-arr[1])*current;
		current=-1;
		for(int i=1;i<(n-1);i++){
			dp[i]=dp[i-1]+(Math.abs(arr[i]-arr[i+1])*current);
			current*=-1;
		}
		Arrays.sort(dp);
		pw.println(Math.max(dp[n-2],dp[n-2]-dp[0]));
	}
	
	public static int fact(int n){
		int ans=1;
		for(int i=1;i<=n;i++) ans=(ans*i)%1000000007;
		return ans;
	}
	//----------------------------------------THE END----------------------------------------------------------//        	
 
	static class Pair implements Comparable<Pair>{
 
		int k,l;
		Pair(int k,int l){
			
			this.k=k;
			this.l=l;
		}
		@Override
		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
		//	Sort in increasing order
 
			return Integer.compare(k,o.k);
			/*if(Math.min(2*o.k, o.l)<Math.min(2*k, l)){
				return -1;
			}
			else if(Math.min(2*o.k, o.l)==Math.min(2*k, l)){
				return 0;
			}else{
				return 1;
			}*/
			
		}
		
		
	}
 
	public static long gcd(long x, long y) {
		if (x % y == 0)
			return y;
		else
			return gcd(y, x % y);
	}
	
	private static int BinarySearch(int a[], int low, int high, int target) {
		if (low > high)
			return -1;
		int mid = low + (high - low) / 2;
		if (a[mid] == target)
			return mid;
		if (a[mid] > target)
			high = mid - 1;
		if (a[mid] < target)
			low = mid + 1;
		return BinarySearch(a, low, high, target);
	}
	
	public static String reverseString(String s) {
		StringBuilder sb = new StringBuilder(s);
		sb.reverse();
		return (sb.toString());
	}

	
	
	public static long pow(long n, long p, long m) {
		long result = 1;
		if (p == 0)
			return 1;
		if (p == 1)
			return n;
		while (p != 0) {
			if (p % 2 == 1)
				result *= n;
			if (result >= m)
				result %= m;
			p >>= 1;
			n *= n;
			if (n >= m)
				n %= m;
		}
		return result;
	}
 
	public static long pow(long n, long p) {
		long result = 1;
		if (p == 0)
			return 1;
		if (p == 1)
			return n;
		while (p != 0) {
			if (p % 2 == 1)
				result *= n;
			p >>= 1;
			n *= n;
		}
		return result;
 
	}

 	public static int[] radixSort(int[] f) {
		int[] to = new int[f.length];
		{
			int[] b = new int[65537];
			for (int i = 0; i < f.length; i++)
				b[1 + (f[i] & 0xffff)]++;
			for (int i = 1; i <= 65536; i++)
				b[i] += b[i - 1];
			for (int i = 0; i < f.length; i++)
				to[b[f[i] & 0xffff]++] = f[i];
			int[] d = f;
			f = to;
			to = d;
		}
		{
			int[] b = new int[65537];
			for (int i = 0; i < f.length; i++)
				b[1 + (f[i] >>> 16)]++;
			for (int i = 1; i <= 65536; i++)
				b[i] += b[i - 1];
			for (int i = 0; i < f.length; i++)
				to[b[f[i] >>> 16]++] = f[i];
			int[] d = f;
			f = to;
			to = d;
		}
		return f;
	}
 
	public static int nextPowerOf2(final int a) {
		int b = 1;
		while (b < a) {
			b = b << 1;
		}
		return b;
	}
 
	public static boolean PointInTriangle(int p1, int p2, int p3, int p4, int p5, int p6, int p7, int p8) {
		int s = p2 * p5 - p1 * p6 + (p6 - p2) * p7 + (p1 - p5) * p8;
		int t = p1 * p4 - p2 * p3 + (p2 - p4) * p7 + (p3 - p1) * p8;
 
		if ((s < 0) != (t < 0))
			return false;
 
		int A = -p4 * p5 + p2 * (p5 - p3) + p1 * (p4 - p6) + p3 * p6;
		if (A < 0.0) {
			s = -s;
			t = -t;
			A = -A;
		}
		return s > 0 && t > 0 && (s + t) <= A;
	}
 
	public static float area(int x1, int y1, int x2, int y2, int x3, int y3) {
		return (float) Math.abs((x1 * (y2 - y3) + x2 * (y3 - y1) + x3 * (y1 - y2)) / 2.0);
	}
 
	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;
	}
 
	//merge Sort
 
	static long sort(int a[])
	{  int n=a.length;
		int b[]=new int[n];	
		return mergeSort(a,b,0,n-1);}
	static long mergeSort(int a[],int b[],long left,long right)
	{ long c=0;if(left<right)
	 {   long mid=left+(right-left)/2;
		 c= mergeSort(a,b,left,mid);
		 c+=mergeSort(a,b,mid+1,right);
		 c+=merge(a,b,left,mid+1,right); }	
		return c;	 }
	static long merge(int a[],int  b[],long left,long mid,long right)
	{long c=0;int i=(int)left;int j=(int)mid; int k=(int)left;
	while(i<=(int)mid-1&&j<=(int)right)
	{ if(a[i]>a[j]) {b[k++]=a[i++]; }
	else	{ b[k++]=a[j++];c+=mid-i;}}
	while (i <= (int)mid - 1)   b[k++] = a[i++]; 
	while (j <= (int)right) b[k++] = a[j++];
	for (i=(int)left; i <= (int)right; i++) 
		a[i] = b[i];  return c;  }

	// 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 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);
	}
		
    	
    }