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.

import java.util.*;
import java.io.*;


public class ProblemC {

    public static int mod = 1000000007;
    public static InputReader in;
    public static PrintWriter out;
    
    static long maxSubArraySum(long a[])
    {
        int size = a.length;
        long max_so_far = Long.MIN_VALUE, max_ending_here = 0;
 
        for (int i = 0; i < size; i++)
        {
            max_ending_here = max_ending_here + a[i];
            if (max_so_far < max_ending_here)
                max_so_far = max_ending_here;
            if (max_ending_here < 0)
                max_ending_here = 0;
        }
        return max_so_far;
    }
    
    public static void main(String[] args) throws FileNotFoundException {

        in = new InputReader(System.in);
        out = new PrintWriter(System.out);
        
        int n=in.nextInt();
        long[] a=in.nextLongArray(n);
        long[] a1=new long[n-1];
        long[] a2=new long[n-2];
        
        for(int i=1;i<n;i++){
            a1[i-1]=Math.abs(a[i]-a[i-1]);
            if(i%2==0) a1[i-1]=-a1[i-1];
        }

        for(int i=1;i<n-1;i++){
            a2[i-1]=-a1[i];
        }
        long ans=Integer.MIN_VALUE;
        ans=max(ans,maxSubArraySum(a1));
        ans=max(ans,maxSubArraySum(a2));
        
        out.println(ans);
        
        out.close();
    }
    
 
    public static void debug(Object... o) {
		System.out.println(Arrays.deepToString(o));
	}
    static class Pair{
            int x;
            int y;
            int i;
            Pair(int x,int y){
                    this.x=x;
                    this.y=y;
            }
            Pair(int x,int y,int i){
                    this.x=x;
                    this.y=y;
                    this.i=i;
            }

        @Override
        public String toString() {
            return x+" "+y;
        }

            
    }

    public static class CompareTable implements Comparator{
        public int compare(Object o1,Object o2){
            Pair p1 = (Pair) o1;
            Pair p2 = (Pair) o2;

            if(p1.x!=p2.x) return Integer.compare(p1.x, p2.x);
            else return Integer.compare(p1.y, p2.y);
        }
    }
    

    public static long add(long x, long y) {
    return (x + y)%mod;
    }

    public static long mul(long x, long y) {
    return (x*y)%mod;
    }
    public static boolean isPal(String s){
        for(int i=0, j=s.length()-1;i<=j;i++,j--){
                if(s.charAt(i)!=s.charAt(j)) return false;
        }
        return true;
    }
    public static String rev(String s){
            StringBuilder sb=new StringBuilder(s);
            sb.reverse();
            return sb.toString();
    }

    public static long gcd(long x,long y){
    if(x%y==0)
            return y;
    else
            return gcd(y,x%y);
    }

    public static int gcd(int x,int y){
    if(x%y==0)
            return y;
    else 
            return gcd(y,x%y);
    }

    public static long gcdExtended(long a,long b,long[] x){

        if(a==0){
            x[0]=0;
            x[1]=1;
            return b;
        }
        long[] y=new long[2];
        long gcd=gcdExtended(b%a, a, y);

        x[0]=y[1]-(b/a)*y[0];
        x[1]=y[0];

        return gcd;
    }

    public static int abs(int a,int b){
    return (int)Math.abs(a-b);
    }

    public static long abs(long a,long b){
    return (long)Math.abs(a-b);
    }

    public static int max(int a,int b){
    if(a>b)
            return a;
    else
            return b;
    }

    public static int min(int a,int b){
    if(a>b)
            return b;
    else 
            return a;
    }

    public static long max(long a,long b){
    if(a>b)
            return a;
    else
            return b;
    }

    public static long min(long a,long b){
    if(a>b)
            return b;
    else 
            return a;
    }

    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;
    }

    static class InputReader {

            private final InputStream stream;
            private final byte[] buf = new byte[8192];
            private int curChar, snumChars;
            private SpaceCharFilter filter;

            public InputReader(InputStream stream) {
                    this.stream = stream;
            }

            public int snext() {
                    if (snumChars == -1)
                            throw new InputMismatchException();
                    if (curChar >= snumChars) {
                            curChar = 0;
                            try {
                                    snumChars = stream.read(buf);
                            } catch (IOException e) {
                                    throw new InputMismatchException();
                            }
                            if (snumChars <= 0)
                                    return -1;
                    }
                    return buf[curChar++];
            }

            public int nextInt() {
                    int c = snext();
                    while (isSpaceChar(c)) {
                            c = snext();
                    }
                    int sgn = 1;
                    if (c == '-') {
                            sgn = -1;
                            c = snext();
                    }
                    int res = 0;
                    do {
                            if (c < '0' || c > '9')
                                    throw new InputMismatchException();
                            res *= 10;
                            res += c - '0';
                            c = snext();
                    } while (!isSpaceChar(c));
                    return res * sgn;
            }

            public long nextLong() {
                    int c = snext();
                    while (isSpaceChar(c)) {
                            c = snext();
                    }
                    int sgn = 1;
                    if (c == '-') {
                            sgn = -1;
                            c = snext();
                    }
                    long res = 0;
                    do {
                            if (c < '0' || c > '9')
                                    throw new InputMismatchException();
                            res *= 10;
                            res += c - '0';
                            c = snext();
                    } while (!isSpaceChar(c));
                    return res * sgn;
            }

            public int[] nextIntArray(int n) {
                    int a[] = new int[n];
                    for (int i = 0; i < n; i++) {
                            a[i] = nextInt();
                    }
                    return a;
            }

            public long[] nextLongArray(int n) {
                    long a[] = new long[n];
                    for (int i = 0; i < n; i++) {
                            a[i] = nextInt();
                    }
                    return a;
            }

            public String readString() {
                    int c = snext();
                    while (isSpaceChar(c)) {
                            c = snext();
                    }
                    StringBuilder res = new StringBuilder();
                    do {
                            res.appendCodePoint(c);
                            c = snext();
                    } while (!isSpaceChar(c));
                    return res.toString();
            }

            public String nextLine() {
                    int c = snext();
                    while (isSpaceChar(c))
                            c = snext();
                    StringBuilder res = new StringBuilder();
                    do {
                            res.appendCodePoint(c);
                            c = snext();
                    } while (!isEndOfLine(c));
                    return res.toString();
            }

            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);
            }
    }
}    


