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.util.*;
import java.io.*;
import java.math.*;
public class Fuck{
	static long MOD=(long)Math.pow(10,9)+7;
	static final int lint=Integer.MAX_VALUE;
	static final double ldouble=Double.MAX_VALUE;
	public static void main(String args[]) {
        new Thread(null, new Runnable() {
            public void run() {
                try{
                    solve();
                }
                catch(Exception e){
                    e.printStackTrace();
                }
            }
        }, "1", 1 << 26).start();
	}
    static InputReader in;
    static PrintWriter w;
    static void solve(){
        in = new InputReader(System.in);
        w = new PrintWriter(System.out);
        int n=in.nextInt();
        long arr[]=new long[n];
        for(int i=0;i<n;i++){
        	arr[i]=in.nextLong();
        }
        long a1[]=new long[n-1];
        long a2[]=new long[n-1];
        for(int i=0;i<n-1;i++){
        	a1[i]=Math.abs(arr[i]-arr[i+1]);
        	if(i%2==0){
        		a2[i]=-a1[i];
        	}else{
        		a2[i]=a1[i];
        		a1[i]=-a1[i];
        	}
        }
        long max=Long.MIN_VALUE;
        long maxsofar=0L;
        for(int i=0;i<a1.length;i++){
        	maxsofar=maxsofar+a1[i];
        	if(maxsofar>max){
        		max=maxsofar;
        	}
        	if(maxsofar<0){
        		maxsofar=0;
        		if((i+1)%2==1){
        			i++;
        		}
        	}
        }
        maxsofar=0L;
        for(int i=1;i<a2.length;i++){
        	maxsofar=maxsofar+a2[i];
        	if(maxsofar>max){
        		max=maxsofar;
        	}
        	if(maxsofar<0){
        		maxsofar=0;
        		if((i+1)%2==0){
        			i++;
        		}
        	}
        }
        w.println(max);
        w.close();
    }
    
//  //if  str2 (pattern) is subsequence of str1 (Text) or not
//	static boolean function(String str1,String str2){
//	     str2 = str2.replace("", ".*");  //returns .*a.*n.*n.*a.
//	     return (str1.matches(str2));  // returns true
//	}
    static double convert(double a){
    	return Math.round(a * 100.0) / 100.0;
    }
    static boolean flag=false;
    static HashSet<Integer> ans;
    static int Arr[];
    static long size[];
  //modified initialize function:
    static void initialize(int N){
    	Arr=new int[N];
    	size=new long[N];
        for(int i = 0;i<N;i++){
        	Arr[ i ] = i ;
        	size[ i ] = 1;
        }
    }
    static boolean find(int A,int B){
        if( root(A)==root(B) )       //if A and B have same root,means they are connected.
        return true;
        else
        return false;
    }
 // modified root function.
    static void weighted_union(int A,int B,int n){
        int root_A = root(A);
        int root_B = root(B);
        if(size[root_A] < size[root_B ]){
        	Arr[ root_A ] = Arr[root_B];
        	size[root_B] += size[root_A];
        }
        else{
        	Arr[ root_B ] = Arr[root_A];
        	size[root_A] += size[root_B];
        }
    }
    static int root (int i){
        while(Arr[ i ] != i){
            Arr[ i ] = Arr[ Arr[ i ] ] ; 
            i = Arr[ i ]; 
        }
        return i;
    }
    
//	static long gcd(long a,long b){
//		if(a==0){
//			return b;
//		}
//		return gcd(b%a,a);
//	}
//	static boolean isPrime[];
////	 //for marking all prime numbers greater than 1 and less than equal to N
//	static void sieve(int N) {
//      isPrime=new boolean[N+1];
//      isPrime[0] = true;
//      isPrime[1] = true;
//      for(int i = 2; i * i <= N; ++i) {
//           if(isPrime[i] == false) {//Mark all the multiples of i as composite numbers
//               for(int j = i * i; j <= N ;j += i)
//                   isPrime[j] = true;
//          }
//      }
//	}
//	static boolean isPrime(long n) {
//		if(n < 2L) return false;
//		if(n == 2L || n == 3L) return true;
//		if(n%2L == 0 || n%3L == 0) return false;	
//		long sqrtN = (long)Math.sqrt(n)+1L;
//		for(long i = 6L; i <= sqrtN; i += 6L) {
//			if(n%(i-1) == 0 || n%(i+1) == 0) return false;
//		}
//		return true;
//	}
//	static HashMap<Integer,Integer> level;;
//	static HashMap<Integer,Integer> parent;
	static int maxlevel=0;
	static ArrayList<Integer> adj[]; //Adjacency Lists
    static int V;   // No. of vertices
    // Constructor
    static void Graph(int v){
        V = v;
        adj = new ArrayList[v];
        for (int i=0; i<v; ++i){
        	adj[i] = new ArrayList();
        }
    }
    // Function to add an edge into the graph
    static void addEdge(int v,int w){
		adj[v].add(w);
//		adj[w].add(v);
    }
    static void bfs(int s,int n){
    	boolean visited[]=new boolean[n];
    	LinkedList<Integer> queue=new LinkedList<Integer>();
    	queue.add(s);
    	visited[s]=true;
    	ans.add(s);
    	while(!queue.isEmpty()){
    		int num=queue.pop();
//    		System.out.println(ans.toString());
    		if(flag){
    			break;
    		}
    		for(int i=0;i<adj[num].size();i++){
    			if(!visited[adj[num].get(i)]){
    				visited[adj[num].get(i)]=true;
    				queue.add(adj[num].get(i));
    				ans.add(adj[num].get(i));
    				if(ans.size()==n){
    					flag=true;
    					break;
    				}
    			}
    		}
    	}
    }
//	static boolean T[][][];
//	static void subsetSum(int input[], int total, int count) {
//        T = new boolean[input.length + 1][total + 1][count+1];
//        for (int i = 0; i <= input.length; i++) {
//        	T[i][0][0] = true;
//        	for(int j = 1; j<=count; j++){
//        		T[i][0][j] = false;
//        	}
//        }
//        int sum[]=new int[input.length+1];
//        for(int i=1;i<=input.length;i++){
//            sum[i]=sum[i-1]+input[i-1];
//        }
//        for (int i = 1; i <= input.length; i++) {
//            for (int j = 1; j <= (int)Math.min(total,sum[i]); j++) {
//            	for (int k = 1; k <= (int)Math.min(i,count); k++){
//            		 if (j >= input[i - 1]) {//Exclude and Include
//                         T[i][j][k] = T[i - 1][j][k] || T[i - 1][j - input[i - 1]][k-1];
//                     } else {
//                         T[i][j][k] = T[i-1][j][k];
//                     }
//            	}
//            }
//        }
//    }
//	static <K,V extends Comparable<? super V>>
//	SortedSet<Map.Entry<K,V>> entriesSortedByValues(Map<K,V> map) {
//	    SortedSet<Map.Entry<K,V>> sortedEntries = new TreeSet<Map.Entry<K,V>>(
//	        new Comparator<Map.Entry<K,V>>() {
//	            @Override public int compare(Map.Entry<K,V> e1, Map.Entry<K,V> e2) {
//	                int res = e2.getValue().compareTo(e1.getValue());
//	                return res != 0 ? res : 1;
//	            }
//	        }
//	    );
//	    sortedEntries.addAll(map.entrySet());
//	    return sortedEntries;
//	}
	
 
	 
	//minimum prime factor of all the numbers less than n
    static int minPrime[];
	static void minimumPrime(int n){
		minPrime=new int[n+1];
		minPrime[1]=1;
        for (int i = 2; i * i <= n; ++i) {
            if (minPrime[i] == 0) {         //If i is prime
                for (int j = i * i; j <= n; j += i) {
                    if (minPrime[j] == 0) {
                        minPrime[j] = i;
                    }
                }
            }
        }
        for (int i = 2; i <= n; ++i) {
            if (minPrime[i] == 0) {
                minPrime[i] = i;
            }
        }
	}
	static long power(long base, long exponent, long modulus){
	    long result = 1;
	    while (exponent > 0) {
	        if (exponent % 2 == 1)
	            result = (result * base) % modulus;
	        exponent = exponent >> 1;
	        base = (base * base) % modulus;
	    }
	    return result;
	}
	static long modInverse(long A, long M)
	{
		long x=extendedEuclid(A,M)[0];
		return (x%M+M)%M;    //x may be negative
	}
	static long[] extendedEuclid(long A, long B) {
		if(B == 0) {
			long d = A;
			long x = 1;
			long y = 0;
			return new long[]{x,y,d};
		}
		else {
			long arr[]=extendedEuclid(B, A%B);
			long temp = arr[0];
			arr[0] = arr[1];
			arr[1] = temp - (A/B)*arr[1];
			return arr;
		}
	}
 
	static class InputReader {
        private final InputStream stream;
        private final byte[] buf = new byte[8192];
        private int curChar, numChars;
        private SpaceCharFilter filter;
 
        public InputReader(InputStream stream) {
            this.stream = stream;
        }
        
        public 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++];
        }
 
        public 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();
        }
 
        public String readString() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }
 
        public 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;
        }
 
        public 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;
        }
 
        public int[] nextIntArray(int n) {
            int[] arr = new int[n];
            for (int i = 0; i < n; i++) {
                arr[i] = nextInt();
            }
            return arr;
        }
 
        public long[] nextLongArray(int n) {
            long[] arr = new long[n];
            for (int i = 0; i < n; i++) {
                arr[i] = nextLong();
            }
            return arr;
        }
 
        public boolean isSpaceChar(int c) {
            if (filter != null)
                return filter.isSpaceChar(c);
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }
 
        private boolean isEndOfLine(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }
        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }
	}
} 
class NodeS{
	char x;
	char y;
	public void setx(char x){
		this.x=x;
	}
	public void sety(char y){
		this.y=y;
	}
	public char getx(){
		return x;
	}
	public char gety(){
		return y;
	}
}