import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            SortedMap<Integer, Integer> array = new TreeMap<>();
            int number;
            for (int i = 0; i < n; i++) {
                number = scanner.nextInt();
                if (!array.containsKey(number)) {
                    array.put(number, 0);
                }
                array.put(number, array.get(number) + 1);
            }
            // processing
            int minDifference = Integer.MAX_VALUE;
            int amountOfNumbers = Integer.MIN_VALUE;
            int firstKey = array.firstKey();
            int secondKey;
            for (Integer currentKey: array.keySet()) {
                if (currentKey == firstKey) {
                    continue;
                }
                secondKey = currentKey;
                if (secondKey - firstKey < minDifference) {
                    minDifference = secondKey - firstKey;
                    amountOfNumbers = array.get(firstKey) +  array.get(secondKey);
                } else if (secondKey - firstKey == minDifference) {
                    if (array.get(firstKey) + array.get(secondKey) > amountOfNumbers) {
                        amountOfNumbers = array.get(firstKey) + array.get(secondKey);
                    }
                }
                // one step ahead
                firstKey = secondKey;
            }

            boolean zeroDifferenceRequired = minDifference != 1;
            if (zeroDifferenceRequired) {
                amountOfNumbers = 0;
            }
            for (SortedMap.Entry<Integer, Integer> entry: array.entrySet()) {
                if (entry.getValue() > amountOfNumbers) {
                    amountOfNumbers = entry.getValue();
                }
            }
            System.out.println(amountOfNumbers);
        }
    }
}