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.text.DecimalFormat;
import java.util.*;
import java.io.*;
import java.math.*;
public class Main {
	public static long mod= (long) (1e9 +7);
	static InputReader s;
	static PrintWriter out;
	static HashMap<Character,String> ans= new HashMap<>();
	public static void main(String args[]) {
		new Thread(null, new Runnable() {
			public void run() {
				try{
					solve();
					out.flush();
					out.close();
				}
				catch(Exception e){
					e.printStackTrace();
				}
			}
		}, "1", 1 << 26).start();
	}
	public static void solve() throws IOException{
		s= new InputReader(System.in);
		OutputStream outputStream= System.out;
		out= new PrintWriter(outputStream);
		int n= s.nextInt();
		int a[]= new int[n];
		for(int i=0;i<n;i++)
			a[i]= s.nextInt();
		long l[]= new long[n];
		long r[]= new long[n];
		for(int i=1;i<n;i++){
			if(i%2==1)
				l[i]= l[i-1] + Math.abs(a[i]-a[i-1]);
			else{
				l[i] = l[i-1] - Math.abs(a[i] - a[i-1]);
			}
			if(l[i]<0)
				l[i]=0;
			
//			System.out.print(l[i]+" ");
		}
		
		for(int i=2;i<n;i++){
			if(i%2==0)
				r[i]= r[i-1] + Math.abs(a[i]-a[i-1]);
			else{
				r[i] = r[i-1] - Math.abs(a[i] - a[i-1]);
			}
			if(r[i]<0)
				r[i]=0;
		}
		long max= Long.MIN_VALUE;
		for(int i=0;i<n;i++){
			max= Math.max(max, l[i]);
			max= Math.max(max, r[i]);
		}
		out.println(max);
	}
	
	static long combinations(long n,long r){   // O(r)
		if(r==0 || r==n) return 1;
		r= Math.min(r, n-r);
		long ans=n;  // nC1=n;
		for(int i=1;i<r;i++){
			ans= ans*(n-i);
			ans= ans/(i+1);
		}
		return ans;	
	}
			
	static long modulo(long x,long y,long p)	
	{
		 long res = 1;
		 x = x % p;  
		 
	    while (y > 0)
	    {
	        if (y%2==1)
	            res = (res*x) % p;
	 
	        y = y>>1;
	        x = (x*x) % p;  
	    }
	    return res;
	}
	

	
	static HashSet<Integer> primeFactors(int n)   // O(sqrt(n))
	{
	    // Print the number of 2s that divide n
		HashSet<Integer> arr= new HashSet<>();
	    while (n%2 == 0)
	    {
	        arr.add(2);
	        n = n/2;
	    }
	 
	    // n must be odd at this point.  So we can skip one element (Note i = i +2)
	    for (int i = 3; i <= Math.sqrt(n); i = i+2)
	    {
	        // While i divides n, print i and divide n
	        while (n%i == 0)
	        {
	            arr.add(i);
	            n = n/i;
	        }
	    }
	    // This condition is to handle the case when n is a prime number
	    // greater than 2
	    if (n > 2)
	        arr.add(n);
	    
	    return arr;
	}
 
	public static long expo(long a, long b){
		if (b==0)
	        return 1;
	    if (b==1)
	        return a;
	    if (b==2)
	        return a*a;
 
	    if (b%2==0){
	            return expo(expo(a,(b/2)),2);
	    }
	    else{
	        return a*expo(expo(a,(b-1)/2),2);
	    }
	}
	static class Pair implements Comparable<Pair>
	{
		long a;
		int b;
//		int c;
		Pair(long aa, int bb)
		{
			a= aa;
			b= bb;
//			c=cc;
		}
		
		public int compareTo(Pair o) 
		{
			int ans = Long.compare(this.a,o.a);
			return ans;
//			return ans==0 ? -Integer.compare(this.b, o.b):ans;
//			if(Long.compare(this.x, o.x)!=0)
//				return -Long.compare(this.x, o.x);
//			else
//				return Long.compare(this.y, o.y);
//			return Integer.compare(this.x, o.x);
	//		return Long.compare(this.x, o.x);
		}
		
		public int hashCode() {
			int hu = (int) (a ^ (a >>> 32));
			int hv = (int) (b ^ (b >>> 32));
			return 31 * hu + hv;
		}
// 
		public boolean equals(Object o) {
			Pair other = (Pair) o;
			return a == other.a && b == other.b;
		}
		
		public String toString() {
			return "[x=" + a + ", y=" + b + "]";
		}
		
	}
	
	public static int[] sieve(int N){    // O(n*log(logn))
		int arr[]= new int[N+1];
		for(int i=2;i<=Math.sqrt(N);i++){
			if(arr[i]==0){
				for(int j= i*i;j<= N;j= j+i){
					arr[j]=1;
				}
			}
		}
		return arr;
		// All the i for which arr[i]==0 are prime numbers.
	}
	static int gcd(int a,int b){       // O(logn)
		if(b==0) return a;
		return gcd(b,a%b);
	}
	
	public static void debug(Object... o) {
		System.out.println(Arrays.deepToString(o));
	}
	
	static void catalan_numbers(int n) {
		long catalan[]= new long[n+1];
	    catalan[1] = 1;
	    for (int i = 2; i <= n; i++) {
	        for (int j = 1; j <= i - 1; j++) {
	            catalan[i] = catalan[i] + ((catalan[j]) * catalan[i - j]);
	        }
	    }
	}
	
	static final class InputReader{
        private final InputStream stream;
        private final byte[] buf=new byte[1024];
        private int curChar;
        private int Chars;
        public InputReader(InputStream stream){this.stream=stream;}
		private int read()throws IOException{
            if(curChar>=Chars){
                curChar=0;
                Chars=stream.read(buf);
                if(Chars<=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[] nextIntBrray(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;
        }
    }
}