When Xellos was doing a practice course in university, he once had to measure the intensity of an effect that slowly approached equilibrium. A good way to determine the equilibrium intensity would be choosing a sufficiently large number of consecutive data points that seems as constant as possible and taking their average. Of course, with the usual sizes of data, it's nothing challenging — but why not make a similar programming contest problem while we're at it?

You're given a sequence of n data points a1, ..., an. There aren't any big jumps between consecutive data points — for each 1 ≤ i < n, it's guaranteed that |ai + 1 - ai| ≤ 1.

A range [l, r] of data points is said to be almost constant if the difference between the largest and the smallest value in that range is at most 1. Formally, let M be the maximum and m the minimum value of ai for l ≤ i ≤ r; the range [l, r] is almost constant if M - m ≤ 1.

Find the length of the longest almost constant range.

Input

The first line of the input contains a single integer n (2 ≤ n ≤ 100 000) — the number of data points.

The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 100 000).

Output

Print a single number — the maximum length of an almost constant range of the given sequence.

Examples

Input

5
1 2 3 3 2


Output

4


Input

11
5 4 5 5 6 7 8 8 8 7 6


Output

5

Note

In the first sample, the longest almost constant range is [2, 5]; its length (the number of data points in it) is 4.

In the second sample, there are three almost constant ranges of length 4: [1, 4], [6, 9] and [7, 10]; the only almost constant range of the maximum length 5 is [6, 10].

import java.io.*;
import java.util.*;
import java.math.BigInteger;
/*
 * This file was created by ayush in attempt to solve the problem problems
 */
public class main {
    public void solve(int n,int[] inp, PrintWriter out) {
	boolean alternate = false;
	boolean nonZero=false;
	int last=0;
	int longest=0;
	int Change=0;
	for(int i=1;i<n;i++){
		if(inp[i]>inp[i-1]){
			if(nonZero && alternate){
				longest = Math.max(longest,i-last);
				last=Change;	
			}
			Change=i;
			nonZero=true;
			alternate=true;
		}else if(inp[i]<inp[i-1]){
			if(nonZero && !alternate){
				longest = Math.max(longest,i-last);
				last=Change;	
			}
			Change=i;
			nonZero=true;
			alternate=false;
		}
	}
	longest=Math.max(longest,n-last);
	out.println(longest);
    }

    public static void main(String[] args) throws Exception {
	
        FastScanner in = new FastScanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        int n = in.nextInt();
        int[] inp = in.nextIntArray();	
        Date t1 = new Date();
        main solver = new main();
        solver.solve(n,inp, out);
        out.flush();
        Date t2 = new Date();
        System.err.println(String.format("Your program took %f seconds", (t2.getTime() - t1.getTime()) / 1000.0));
        out.close();
	
		
	
    }
    static class FastScanner {

    private static BufferedReader reader;
    private static StringTokenizer tokenizer;


    public FastScanner(InputStream in) throws Exception {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = new StringTokenizer(reader.readLine().trim());
    }

    public int numTokens() throws Exception {
        if (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine().trim());
            return numTokens();
        }
        return tokenizer.countTokens();
    }

    public boolean hasNext() throws Exception {
        if (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine().trim());
            return hasNext();
        }
        return true;
    }

    public String next() throws Exception {
        if (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine().trim());
            return next();
        }
        return tokenizer.nextToken();
    }

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

    public float nextFloat() throws Exception {
        return Float.parseFloat(next());
    }

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

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

    public int[] nextIntArray() throws Exception {
        String[] line = reader.readLine().trim().split(" ");
        int[] out = new int[line.length];
        for (int i = 0; i < line.length; i++) {
            out[i] = Integer.valueOf(line[i]);
        }
        return out;
    }

    public double[] nextDoubleArray() throws Exception {
        String[] line = reader.readLine().trim().split(" ");
        double[] out = new double[line.length];
        for (int i = 0; i < line.length; i++) {
            out[i] = Double.valueOf(line[i]);
        }
        return out;
    }

    public Integer[] nextIntegerArray() throws Exception {
        String[] line = reader.readLine().trim().split(" ");
        Integer[] out = new Integer[line.length];
        for (int i = 0; i < line.length; i++) {
            out[i] = Integer.valueOf(line[i]);
        }
        return out;
    }

    public BigInteger[] nextBigIngtegerArray() throws Exception {
        String[] line = reader.readLine().trim().split(" ");
        BigInteger[] out = new BigInteger[line.length];
        for (int i = 0; i < line.length; i++) {
            out[i] = new BigInteger(line[i]);
        }
        return out;
    }

    public String nextLine() throws Exception {
        return reader.readLine().trim();
    }

    public BigInteger nextBigInteger() throws Exception {
        return new BigInteger(next());
    }
    }


   


    static class DEBUG {
        public static void DebugInfo(String disp) {
            System.err.println("DEBUG Info: " + disp);
        }

        public static void DebugVariable(String variable, String value) {
            System.err.println("DEBUG Info: " + variable + " => " + value);
        }


        public static void DebugVariable(String variable, int value) {
            System.err.println("DEBUG Info: " + variable + " => " + value);
        }


        public static void DebugVariable(String variable, long value) {
            System.err.println("DEBUG Info: " + variable + " => " + value);
        }

        public static void DebugArray(int[] value) {
            for (int i = 0; i < value.length; i++) {

                System.err.println("DEBUG Info: " + i + " => " + value[i]);
            }
        }

    }

}
