Problem: You are a coach at your local university. There are n students under your supervision, the programming skill of the i-th student is a_i.

You have to create a team for a new programming competition. As you know, the more students some team has the more probable its victory is! So you have to create a team with the maximum number of students. But you also know that a team should be balanced. It means that the programming skill of each pair of students in a created team should differ by no more than 5.

Your task is to report the maximum possible number of students in a balanced team.

Input

The first line of the input contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of students.

The second line of the input contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ 10^9), where a_i is a programming skill of the i-th student.

Output

Print one integer — the maximum possible number of students in a balanced team.

Examples

Input


6
1 10 17 12 15 2


Output


3


Input


10
1337 1337 1337 1337 1337 1337 1337 1337 1337 1337


Output


10


Input


6
1 1000 10000 10 100 1000000000


Output


1

Note

In the first example you can create a team with skills [12, 17, 15].

In the second example you can take all students in a team because their programming skills are equal.

In the third example you can create a team consisting of a single student (and you cannot create a team consisting of at least two students).

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.PriorityQueue;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author caoash
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        FastScanner in = new FastScanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        EKBalancedTeams solver = new EKBalancedTeams();
        solver.solve(1, in, out);
        out.close();
    }

    static class EKBalancedTeams {
        public void solve(int testNumber, FastScanner br, PrintWriter pw) {
            int n = br.nextInt();
            int k = br.nextInt();
            int[] a = br.nextSortedIntArray(n);
            long[][] dp = new long[k + 1][n + 1];
            for (int i = 0; i <= k; i++) {
                for (int j = 0; j <= n; j++) {
                    dp[i][j] = Integer.MIN_VALUE;
                }
            }
            for (int i = 0; i <= n; i++) dp[0][i] = 0;
            for (int i = 1; i <= k; i++) {
                int p1 = 1;
                int p2 = 1;
                while (p1 <= p2 && p2 <= n) {
                    if (a[p2 - 1] - a[p1 - 1] > 5) {
                        p1++;
                    } else {
                        dp[i][p2] = Math.max(dp[i][p2], dp[i - 1][p1 - 1] + (p2 - p1 + 1));
                        p2++;
                    }
                }
                for (int j = 1; j <= n; j++) dp[i][j] = Math.max(dp[i][j], dp[i][j - 1]);
            }
            long ans = 0;
            for (int i = 1; i <= k; i++) {
                for (int j = 1; j <= n; j++) {
                    ans = Math.max(ans, dp[i][j]);
                }
            }
            pw.println(ans);
            pw.close();
        }

    }

    static class FastScanner {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private FastScanner.SpaceCharFilter filter;

        public FastScanner(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 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 boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

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

        public int[] nextSortedIntArray(int n) {
            int array[] = nextIntArray(n);
            PriorityQueue<Integer> pq = new PriorityQueue<Integer>();
            for (int i = 0; i < n; i++) {
                pq.add(array[i]);
            }
            int[] out = new int[n];
            for (int i = 0; i < n; i++) {
                out[i] = pq.poll();
            }
            return out;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }
}