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



public class Main {



    public static void main(String[] args) {
        InputReader in = new InputReader(System.in);
        OutputWriter out = new OutputWriter(System.out);
        int n = in.nextInt();
        int[]a = new int[n];
       int[]values = new int[100001];

        for (int i =0;i<n;i++) {
            a[i] = in.nextInt();


        }
        int p0=0;
        int p1=0;
        int max=0;
        int ans=0;
        int min=Integer.MAX_VALUE;
        while (p0<n)
        {
            while (p1<n)
            {
                max=Math.max(max,a[p1]);
                min=Math.min(min,a[p1]);
                if (max-min>1)
                {
                    break;
                }
                values[a[p1]]++;
                ans=Math.max(ans,p1-p0+1);
                p1++;
            }
            values[a[p0]]--;
            if (values[a[p0]]==0)
            {
                if (max==a[p0])
                {
                    max--;
                    if (max>0&&values[max]==0)
                        max--;
                }
                if (min==a[p0])
                {
                    min++;
                    if (min<100000&&values[min]==0)
                        min++;
                }

            }

            p0++;
        }
        out.printLine(ans);


        out.flush();

    }



    static void MergeSort(int[] a, int[] b,  int p, int r)
    {
        if (p < r)
        {
            int q = (r + p) / 2;
            MergeSort(a, b,  p, q);
            MergeSort(a, b,  q + 1, r);
            Merge(a, b,  p, q, r);
        }
    }
    static void Merge(int[] a, int[] b, int p, int q, int r)
    {
        int n1 = q - p + 1;
        int n2 = r - q;
        int[] R = new int[n1 + 1];
        int[] L = new int[n2 + 1];
        int[] R1 = new int[n1];
        int[] L1 = new int[n2];
        for (int i = 0; i < n1; i++)
        {
            R[i] = a[p + i];
            R1[i] = b[p + i];

        }
        R[n1] = Integer.MAX_VALUE;
        for (int i = 0; i < n2; i++)
        {
            L[i] = a[q + i + 1];
            L1[i] = b[q + i + 1];

        }
        L[n2] =Integer.MAX_VALUE;
        int n = a.length;
        int j = 0;
        int k = 0;
        for (int i = p; i <= r; i++)
        {
            if (L[j] < R[k])
            {
                a[i] = L[j];
                b[i] = L1[j];

                j++;
            }
            else
            {
                a[i] = R[k];
                b[i] = R1[k];

                k++;
            }

        }
    }

}

class Graph {


    int n;
    ArrayList<Integer>[] adjList;

    public Graph(int n) {
        this.n = n;
        adjList = new ArrayList[n];
        for (int i = 0; i < n; i++)
            adjList[i] = new ArrayList<>();
    }

}
class pair  implements Comparable
{

    int key;
    int value;
    public pair(Object key, Object value) {

        this.key = (int)key;
        this.value=(int)value;
    }

    @Override
    public int compareTo(Object o) {
        pair temp =(pair)o;
        return  key-temp.key;
    }
}
class InputReader {

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

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

    public int read() {
        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 = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public long nextLong() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        long res = 0;
        do {
            res *= 10;
            res += c - '0';
            c = read();
        } 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 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 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 boolean isSpaceChar(int c) {
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    private boolean isEndOfLine(int c) {
        return c == '\n' || c == '\r' || c == -1;
    }

}

class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void print(Object... objects) {
        for (int i = 0; i < objects.length; i++) {
            if (i != 0)
                writer.print(' ');
            writer.print(objects[i]);
        }
    }

    public void printLine(Object... objects) {
        print(objects);
        writer.println();
    }

    public void close() {
        writer.close();
    }

    public void flush() {
        writer.flush();
    }

}