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.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class C407 {
	public static void main(String args[]) throws FileNotFoundException {
		InputReader in = new InputReader(System.in);
		OutputStream outputStream = System.out;
		PrintWriter out = new PrintWriter(outputStream);
		StringBuilder sb = new StringBuilder();
		// ----------My Code----------
		int n = in.nextInt();
		long arr[] = in.nextLongArray(n, 0);

		long diff[] = new long[n - 1];
		for (int i = 0; i < n - 1; i++) {
			diff[i] = (int) Math.abs(arr[i + 1] - arr[i]);
			if(i%2==0)
				diff[i]=-diff[i];
		}
		
		long ans1=maxSubArraySum(diff);
		for (int i = 0; i < n - 1; i++) {
			diff[i]=-diff[i];
		}
		long ans2=maxSubArraySum(diff);
		out.println(Math.max(ans1, ans2));
		// ---------------The End------------------

		out.close();
	}

	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;
	}
	// ---------------Extra Methods------------------

	public static long pow(long x, long n, long mod) {
		long res = 1;
		x %= mod;
		while (n > 0) {
			if (n % 2 == 1) {
				res = (res * x) % mod;
			}
			x = (x * x) % mod;
			n /= 2;
		}
		return res;
	}

	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;
	}
	// ---------------Extra Methods------------------

	public static void debug(Object... o) {
		System.out.println(Arrays.deepToString(o));
	}

	static class InputReader {
		public BufferedReader reader;
		public StringTokenizer tokenizer;

		public InputReader(InputStream inputstream) {
			reader = new BufferedReader(new InputStreamReader(inputstream));
			tokenizer = null;
		}

		public String nextLine() {
			String fullLine = null;
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					fullLine = reader.readLine();
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
				return fullLine;
			}
			return fullLine;
		}

		public String next() {
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					tokenizer = new StringTokenizer(reader.readLine());
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
			return tokenizer.nextToken();
		}

		public char nextChar() {
			return next().charAt(0);
		}

		public long nextLong() {
			return Long.parseLong(next());
		}

		public int nextInt() {
			return Integer.parseInt(next());
		}

		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public int[] nextIntArray(int n, int f) {
			if (f == 0) {
				int[] arr = new int[n];
				for (int i = 0; i < n; i++) {
					arr[i] = nextInt();
				}
				return arr;
			} else {
				int[] arr = new int[n + 1];
				for (int i = 1; i < n + 1; i++) {
					arr[i] = nextInt();
				}
				return arr;
			}
		}

		public long[] nextLongArray(int n, int f) {
			if (f == 0) {
				long[] arr = new long[n];
				for (int i = 0; i < n; i++) {
					arr[i] = nextLong();
				}
				return arr;
			} else {
				long[] arr = new long[n + 1];
				for (int i = 1; i < n + 1; i++) {
					arr[i] = nextLong();
				}
				return arr;
			}

		}

		public double[] nextDoubleArray(int n, int f) {
			if (f == 0) {
				double[] arr = new double[n];
				for (int i = 0; i < n; i++) {
					arr[i] = nextDouble();
				}
				return arr;
			} else {
				double[] arr = new double[n + 1];
				for (int i = 1; i < n + 1; i++) {
					arr[i] = nextDouble();
				}
				return arr;
			}
		}

	}

	static class Pair implements Comparable<Pair> {
		int a, b;

		Pair(int a, int b) {
			this.a = a;
			this.b = b;
		}

		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			if (this.a != o.a)
				return Integer.compare(this.a, o.a);
			else
				return Integer.compare(this.b, o.b);
		}

		public boolean equals(Object o) {
			if (o instanceof Pair) {
				Pair p = (Pair) o;
				return p.a == a && p.b == b;
			}
			return false;
		}

		public int hashCode() {
			return new Integer(a).hashCode() * 31 + new Integer(b).hashCode();
		}

	}

}
